42 results on '"Luis Graca"'
Search Results
2. Identification of Human T Follicular Cells in Ectopic Lymphoid Structures
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Rodrigo, Pedroso, Filipa, Ribeiro, Ana Rita, Pires, Luis, Graca, and Valter R, Fonseca
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B-Lymphocytes ,Sjogren's Syndrome ,T Follicular Helper Cells ,Humans ,T-Lymphocytes, Helper-Inducer ,Germinal Center ,T-Lymphocytes, Regulatory ,Autoimmune Diseases - Abstract
T follicular helper (Tfh) and T follicular regulatory (Tfr) cells are the two T cell subsets able to interact with B cells driving germinal center (GC) reactions. These T-B interactions are important for protective immune responses within secondary lymphoid tissue. However, the pathological emergence of ectopic lymphoid structures (ELS) that characterize several autoimmune diseases also involves Tfh and Tfr cells. ELS, often with ectopic GCs, can be identified through biopsies. Sjögren's syndrome (SS) is an example of an autoimmune disease where minor salivary gland (MSG) biopsies are often performed for diagnosis and where ELS can be found. Here, we describe a protocol to identify and isolate T follicular cells from MSGs by flow cytometry and immunohistochemistry.
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- 2021
3. Identification of Human Blood and Tissue T Follicular Regulatory (Tfr) Cells by Flow Cytometry
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Filipa, Ribeiro, Pedro, Ávila-Ribeiro, João Eurico, Fonseca, and Luis, Graca
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Humans ,T-Lymphocytes, Helper-Inducer ,Flow Cytometry ,Germinal Center ,T-Lymphocytes, Regulatory ,Immunity, Humoral ,Immunophenotyping - Abstract
T follicular helper (Tfh) cells and T follicular regulatory (Tfr) cells are crucially involved in the regulation of germinal center reactions. Thus, as key players, the assessment of these cell subsets is necessary for a better understanding of the humoral immune response. Flow cytometry (FC) is one of the most used techniques to perform immunophenotypic analysis, allowing the simultaneous study of different proteins by using multicolor fluorescent panels. Here, we describe an approach to identify Tfr cells from human blood and tissues, namely tonsil and lymph node, by flow cytometry.
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- 2021
4. Modulation of CD4 T cell function via CD6-targeting
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S. Almeida, Afonso P. Basto, Vanessa G. Oliveira, Kalet León, Rita F. Santos, Luis Graca, Carine M. Gonçalves, Jesus Corria-Osorio, Raquel F. Freitas, Alexandre M. Carmo, Tânia Carvalho, and Instituto de Investigação e Inovação em Saúde
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Antigens, Differentiation, T-Lymphocyte ,CD4-Positive T-Lymphocytes ,Fetal Proteins ,CD4-Positive T-Lymphocytes / metabolism ,0301 basic medicine ,Research paper ,Lymphocyte Activation ,Immunological synapse ,Mice ,0302 clinical medicine ,T-Lymphocyte Subsets ,Cell Adhesion Molecules, Neuronal / metabolism ,Antigens, Differentiation, T-Lymphocyte / metabolism ,Cd4 t cell ,EAE ,FOXP3 ,Cell Differentiation ,General Medicine ,T-cell polarization ,Cell biology ,medicine.anatomical_structure ,Foxp3 ,030220 oncology & carcinogenesis ,Antibody ,Cell Adhesion Molecules, Neuronal ,T cell ,CD4 T cells ,Mice, Transgenic ,Biology ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Antigens, CD ,In vivo ,CD4-Positive T-Lymphocytes / immunology ,medicine ,Animals ,Humans ,T-Lymphocyte Subsets / metabolism ,Antigens, CD / metabolism ,CD4-Positive T-Lymphocytes / cytology ,CD6 ,Fetal Proteins / metabolism ,In vitro ,030104 developmental biology ,biology.protein ,Treg cells ,Biomarkers ,Function (biology) ,T-Lymphocyte Subsets / immunology - Abstract
In recent years molecules involved on the immune synapse became successful targets for therapeutic immune modulation. CD6 has been extensively studied, yet, results regarding CD6 biology have been controversial, in spite of the ubiquitous presence of this molecule on virtually all CD4 T cells. We investigated the outcome of murine and human antibodies targeting CD6 domain 1. We found that CD6-targeting had a major impact on the functional specialization of CD4 cells, both human and murine. Differentiation of CD4 T cells towards a Foxp3+ Treg fate was prevented with increasing doses of anti-CD6, while Th1 polarization was favoured. No impact was observed on Th2 or Th17 specialization. These in vitro results provided an explanation for the dose-dependent outcome of in vivo anti-CD6 administration where the anti-inflammatory action is lost at the highest doses. Our data show that therapeutic targeting of the immune synapse may lead to paradoxical dose-dependent effects due to modification of T cell fate. Funded by UID/BIM/50005/2019, project funded by Fundação para a Ciência e a Tecnologia (FCT) / Ministério da Ciência, Tecnologia e Ensino Superior (MCTES) throught Fundos do Orçamento do Estado, pela Fundação para a Ciência e a Tecnologia (FCT) ( PTDC/DTP-FTO/3080/2014 ); and by the project SRecognite Infect - ERA/0003/2015 using national funds through FCT . Funders did not have a role in study design, data collection, analysis, and interpretation, or in the writing of the manuscript.
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- 2019
5. Developmental bifurcation of human T follicular regulatory cells
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Margarida Gama-Carvalho, F. N. Ribeiro, Saumya Kumar, Ana Agua-Doce, Tomás Gomes, Marta Monteiro, Ricardo J. Miragaia, Luis Graca, Eliane Piaggio, Elodie Segura, Sarah A. Teichmann, Afonso P. Basto, Válter R. Fonseca, and Dikélélé Elessa
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0301 basic medicine ,Adult ,T cell ,Immunology ,Palatine Tonsil ,T-Lymphocytes, Regulatory ,Transcriptome ,Affinity maturation ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,Follicular phase ,medicine ,Humans ,RNA-Seq ,Child ,biology ,Cell growth ,Germinal center ,Cell Differentiation ,General Medicine ,T-Lymphocytes, Helper-Inducer ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,biology.protein ,Lymph Nodes ,Antibody - Abstract
Germinal centers (GCs) are anatomic structures where B cells undergo affinity maturation, leading to production of high-affinity antibodies. The balance between T follicular helper (TFH) and regulatory (TFR) cells is critical for adequate control of GC responses. The study of human TFH and TFR cell development has been hampered because of the lack of in vitro assays reproducing in vivo biology, along with difficult access to healthy human lymphoid tissues. We used a single-cell transcriptomics approach to study the maturation of TFH and TFR cells isolated from human blood, iliac lymph nodes (LNs), and tonsils. As independent tissues have distinct proportions of follicular T cells in different maturation states, we leveraged the heterogeneity to reconstruct the maturation trajectory for human TFH and TFR cells. We found that the dominant maturation of TFR cells follows a bifurcated trajectory from precursor Treg cells, with one arm of the bifurcation leading to blood TFR cells and the other leading to the most mature GC TFR cells. Overall, our data provide a comprehensive resource for the transcriptomics of different follicular T cell populations and their dynamic relationship across different tissues.
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- 2020
6. The contribution of B cells to transplantation tolerance
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Luis Graca
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0301 basic medicine ,Graft Rejection ,Naive B cell ,Biology ,Immune tolerance ,03 medical and health sciences ,0302 clinical medicine ,In vivo ,medicine ,Immune Tolerance ,Animals ,Humans ,B cell ,B-Lymphocytes ,Graft rejection ,Infant, Newborn ,General Medicine ,Phenotype ,Tissue Donors ,Transplantation ,surgical procedures, operative ,030104 developmental biology ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,Immunology ,Heart Transplantation ,Transplantation Tolerance ,Research Article - Abstract
The absence of alloantibodies is a feature of transplantation tolerance. Although the lack of T cell help has been evoked to explain this absence, herein we provide evidence for B cell–intrinsic tolerance mechanisms. Using a murine model of heart tolerance, we showed that alloreactive B cells were not deleted but rapidly lost their ability to differentiate into germinal center B cells and secrete donor-specific antibodies. We inferred that tolerant alloreactive B cells retained their ability to sense alloantigen because they continued to drive T cell maturation into CXCR5(+)PD-1(+) T follicular helper cells. Unexpectedly, dysfunctional alloreactive B cells acquired the ability to inhibit antibody production by new naive B cells in an antigen-specific manner. Thus, tolerant alloreactive B cells contribute to transplantation tolerance by foregoing germinal center responses while retaining their ability to function as antigen-presenting cells and by actively suppressing de novo alloreactive B cell responses.
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- 2020
7. The role of TNFR2 and DR3 in the in vivo expansion of tregs in T Cell depleting transplantation regimens
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Pascal Schneider, Leo Buhler, Luis Graca, Jose-Ignacio Rodriguez-Barbosa, José A. Pérez-Simón, Maria-Luisa del Rio, Repositório da Universidade de Lisboa, European Commission, Instituto de Salud Carlos III, Ministerio de Sanidad, Servicios Sociales e Igualdad (España), Junta de Castilla y León, Swiss National Science Foundation, Centro de Investigación Biomédica en Red Cáncer (España), Universidad de Sevilla. Departamento de Medicina, European Union ERDF/ESF, Fondo de Investigaciones Sanitarias, Ministry of Health, Spanish Government, Gerencia Regional de Salud, Spanish National Network CIBER-ONC (oncology research), Unit of Excellence Research UIC (Department of Education of the Regional Government, Junta de Castilla y Leon) 012, [Rodriguez-Barbosa,JI, del Rio,ML] Transplantation Immunobiology, School of Biology and Biotechnology, Institute of Molecular Biology, Genomics and Proteomics, University of Leon, Leon, Spain. [Schneider,P] Department of Biochemistry, University of Lausanne, Epalinges, Switzerland. [Graca,L] School of Medicine, Institute of Molecular Medicine, University of Lisbon, Lisbon, Portugal. [Bühler L] Faculty of Science and Medicine, Section of Medicine, University of Fribourg, Fribourg, Switzerland. [Perez-Simon,JA] Department of Hematology, Institute of Biomedicine (IBIS/CSIC), University Hospital Virgen del Rocio, Sevilla, Spain, and This work has been supported by grant FIS PI13/00029 (Fondo de Investigaciones Sanitarias, Ministry of Health, Spanish Government and co-funded by European Union ERDF/ESF, 'Investing in your future'), LE093U13 and Unit of Excellence Research UIC #012 (Department of Education of the Regional Government, Junta de Castilla y Leon), and Gerencia Regional de Salud (BIO/01/15) to JIRB. It was also funded by FIS PI16/00002 (Instituto de Salud Carlos III and co-funded by European Union ERDF/ESF, 'Investing in your future') and Gerencia Regional de Salud GRS963/A/2014, GRS1142/A/2015 and GRS 1505/A/2017 to M.L.R.G. This work has been supported with funding from the Spanish National Network CIBER-ONC (oncology research) CB16/12/00480 to JAPS. PS is supported by the Swiss National Science Foundation (grant 31003A-176526).
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0301 basic medicine ,Phenomena and Processes::Cell Physiological Phenomena::Cell Physiological Processes::Cell Differentiation [Medical Subject Headings] ,Transplantation Conditioning ,Anatomy::Cells::Blood Cells::Leukocytes::Leukocytes, Mononuclear::Lymphocytes::T-Lymphocytes::T-Lymphocyte Subsets::T-Lymphocytes, Regulatory [Medical Subject Headings] ,medicine.medical_treatment ,Phenomena and Processes::Physiological Phenomena::Physiological Processes::Growth and Development::Growth::Cell Growth Processes::Cell Proliferation::Cell Division [Medical Subject Headings] ,Chemicals and Drugs::Amino Acids, Peptides, and Proteins::Proteins::Membrane Proteins::Receptors, Cell Surface::Receptors, Immunologic::Receptors, Cytokine::Receptors, Tumor Necrosis Factor::Receptors, Tumor Necrosis Factor, Member 25 [Medical Subject Headings] ,Review ,Anatomy::Body Regions::Transplants::Allografts [Medical Subject Headings] ,T-Lymphocytes, Regulatory ,Graft-versus-host disease ,Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Primates::Haplorhini::Catarrhini::Hominidae::Humans [Medical Subject Headings] ,Chemicals and Drugs::Biological Factors::Intercellular Signaling Peptides and Proteins::Tumor Necrosis Factors::Tumor Necrosis Factor-alpha [Medical Subject Headings] ,lcsh:Chemistry ,Mice ,0302 clinical medicine ,Organisms::Eukaryota::Animals [Medical Subject Headings] ,Homeostasis ,lcsh:QH301-705.5 ,Spectroscopy ,Bone Marrow Transplantation ,Phenomena and Processes::Immune System Phenomena::Immune System Processes::Transplantation Immunology [Medical Subject Headings] ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Surgical Procedures, Operative::Transplantation::Organ Transplantation::Heart Transplantation [Medical Subject Headings] ,Phenomena and Processes::Immune System Phenomena::Immune System Processes::Immunomodulation::Immune Tolerance [Medical Subject Headings] ,Diseases::Hemic and Lymphatic Diseases::Hematologic Diseases::Leukocyte Disorders::Leukopenia::Lymphopenia [Medical Subject Headings] ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Models, Theoretical::Models, Biological::Models, Immunological [Medical Subject Headings] ,CD28 ,Immunosuppression ,hemic and immune systems ,Cell Differentiation ,General Medicine ,Regulatory T cells ,Allografts ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Biological Therapy::Immunomodulation::Immunotherapy::Immunosuppression::Transplantation Conditioning [Medical Subject Headings] ,Adoptive Transfer ,Computer Science Applications ,Homeostatic proliferation ,Tolerance induction ,medicine.anatomical_structure ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Surgical Procedures, Operative::Transplantation::Tissue Transplantation::Bone Marrow Transplantation [Medical Subject Headings] ,surgical procedures, operative ,Lymphocyte Transfusion ,Graft rejection ,Cell Division ,Linfocitos T reguladores ,Proliferación celular ,T cell ,TNF/TNF receptors ,Enfermedad injerto contra huésped ,Catalysis ,Lymphocyte Depletion ,Inorganic Chemistry ,Abatacept ,03 medical and health sciences ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Therapeutics::Biological Therapy::Blood Transfusion::Blood Component Transfusion::Leukocyte Transfusion::Lymphocyte Transfusion [Medical Subject Headings] ,Immune system ,Transplantation Immunology ,Lymphopenia ,medicine ,Immune Tolerance ,Animals ,Humans ,Receptors, Tumor Necrosis Factor, Type II ,Physical and Theoretical Chemistry ,Linfopenia ,Molecular Biology ,Receptors, Tumor Necrosis Factor, Member 25 ,Organisms::Eukaryota::Animals::Chordata::Vertebrates::Mammals::Rodentia::Muridae::Murinae::Mice [Medical Subject Headings] ,Transplantation ,Rechazo de injerto ,business.industry ,Tumor Necrosis Factor-alpha ,Organic Chemistry ,Models, Immunological ,Receptores del factor de necrosis tumoral ,medicine.disease ,Chemicals and Drugs::Biological Factors::Antigens::Antigens, Surface::Antigens, Differentiation::Antigens, CD::Receptors, Tumor Necrosis Factor, Type II [Medical Subject Headings] ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Immunologic Techniques::Immunization::Immunization, Passive::Adoptive Transfer [Medical Subject Headings] ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,Cancer research ,Trasplante ,Heart Transplantation ,Phenomena and Processes::Immune System Phenomena::Immune System Processes::Transplantation Immunology::Host vs Graft Reaction::Graft Rejection [Medical Subject Headings] ,Analytical, Diagnostic and Therapeutic Techniques and Equipment::Investigative Techniques::Immunologic Techniques::Immunosuppression::Lymphocyte Depletion [Medical Subject Headings] ,business ,Phenomena and Processes::Physiological Phenomena::Physiological Processes::Homeostasis [Medical Subject Headings] ,030215 immunology - Abstract
This article belongs to the Special Issue Trends in Molecular Research for Transplantation Immunology., Regulatory T cells (Tregs) are essential for the maintenance of tolerance to self and non-self through cell-intrinsic and cell-extrinsic mechanisms. Peripheral Tregs survival and clonal expansion largely depend on IL-2 and access to co-stimulatory signals such as CD28. Engagement of tumor necrosis factor receptor (TNFR) superfamily members, in particular TNFR2 and DR3, contribute to promote peripheral Tregs expansion and sustain their survival. This property can be leveraged to enhance tolerance to allogeneic transplants by tipping the balance of Tregs over conventional T cells during the course of immune reconstitution. This is of particular interest in peri-transplant tolerance induction protocols in which T cell depletion is applied to reduce the frequency of alloreactive T cells or in conditioning regimens that allow allogeneic bone marrow transplantation. These conditioning regimens are being implemented to limit long-term side effects of continuous immunosuppression and facilitate the establishment of a state of donor-specific tolerance. Lymphopenia-induced homeostatic proliferation in response to cytoreductive conditioning is a window of opportunity to enhance preferential expansion of Tregs during homeostatic proliferation that can be potentiated by agonist stimulation of TNFR., This work has been supported by grant FIS PI13/00029 (Fondo de Investigaciones Sanitarias, Ministry of Health, Spanish Government and co-funded by European Union ERDF/ESF, “Investing in your future”), LE093U13 and Unit of Excellence Research UIC #012 (Department of Education of the Regional Government, Junta de Castilla y Leon), and Gerencia Regional de Salud (BIO/01/15) to JIRB. It was also funded by FIS PI16/00002 (Instituto de Salud Carlos III and co-funded by European Union ERDF/ESF, “Investing in your future”) and Gerencia Regional de Salud GRS963/A/2014, GRS1142/A/2015 and GRS 1505/A/2017 to M.L.R.G. This work has been supported with funding from the Spanish National Network CIBER-ONC (oncology research) CB16/12/00480 to JAPS. PS is supported by the Swiss National Science Foundation (grant 31003A-176526).
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- 2020
8. Maturation and phenotypic heterogeneity of human CD4+ regulatory T cells from birth to adulthood and after allogeneic stem cell transplantation
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Tiago R. Matos, Masahiro Hirakawa, Ana C. Alho, Lars Neleman, Luis Graca, Jerome Ritz, Repositório da Universidade de Lisboa, Dermatology, Amsterdam institute for Infection and Immunity, and AII - Infectious diseases
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Adult ,Male ,lcsh:Immunologic diseases. Allergy ,medicine.medical_treatment ,T cell ,Immunology ,Graft vs Host Disease ,chemical and pharmacologic phenomena ,ComputingMilieux_LEGALASPECTSOFCOMPUTING ,Hematopoietic stem cell transplantation ,Biology ,T-Lymphocytes, Regulatory ,Umbilical cord ,Young Adult ,medicine ,Humans ,Transplantation, Homologous ,Immunology and Allergy ,Mass cytometry ,Cells, Cultured ,Treg - regulatory T cell ,alloHSCT ,Original Research ,Aged ,GvHD ,Diversity ,Genetic heterogeneity ,Hematopoietic Stem Cell Transplantation ,hemic and immune systems ,Middle Aged ,CD4 ,Transplantation ,Phenotype ,medicine.anatomical_structure ,Cord blood ,CD4 Antigens ,Female ,Single-Cell Analysis ,Stem cell ,Heterogeneity ,lcsh:RC581-607 - Abstract
Copyright © 2021 Matos, Hirakawa, Alho, Neleman, Graca and Ritz. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms., CD4+ Regulatory T cells (Treg) play a critical role in maintaining immune homeostasis. Various Treg subsets have been identified, however the heterogeneity of Treg subpopulations during development remains uncharacterized. Using mass cytometry we obtained single cell data on expression of 35 functional markers to examine the heterogeneity of Treg cells at birth and in adults. Unsupervised clustering algorithms FlowSOM and ACCENSE were used to quantify Treg heterogeneity. As expected, Treg in umbilical cord blood were predominately naïve while Treg in adult blood were predominately central memory and effector memory cells. Although umbilical cord blood Treg are mostly naïve cells, we observed multiple phenotypic Treg subsets in cord blood. Nevertheless, peripheral blood in adults contained higher percentages of Treg and the heterogeneity of Treg was significantly increased in adults. We also studied Treg heterogeneity throughout a 2-year period after allogeneic hematopoietic stem cell transplantation (alloHSCT) and in patients with chronic graft-versus-host disease (cGVHD). Treg heterogeneity recovered rapidly after alloHSCT and gradually increased in the first two years post-transplant. However, patients with cGVHD had significantly fewer distinct Treg subpopulations, proposing a correlation between a disrupted Treg heterogeneity and cGVHD. Our study is the first to compare human Treg heterogeneity at birth, in healthy adults and in patients after alloHSCT with and without cGVHD. This approach to characterize Treg heterogeneity based on expression of a large panel of functional markers may enable future studies to identify specific Treg defects that contribute to immune dysfunction., This work was supported by NIH grant P01CA229092, EADV Research Fellowship, Rene-Touraine Fellowship and a generous contribution from the Fundação para a Ciência e a Tecnologia (FCT), FCT SFRH/BD/98980/2013
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- 2020
9. Blocking IL-2 Signal In Vivo with an IL-2 Antagonist Reduces Tumor Growth through the Control of Regulatory T Cells
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Tania Carmenate, Kalet León, Karina García-Martínez, Luis Graca, Michel Enamorado, Ernesto Moreno, Janet Avellanet, and Yaquelín Ortiz
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0301 basic medicine ,T cell ,medicine.medical_treatment ,Immunology ,T-Lymphocytes, Regulatory ,Cell Line ,Mice ,03 medical and health sciences ,Immune system ,Cancer immunotherapy ,Immunity ,In vivo ,Cell Line, Tumor ,Neoplasms ,medicine ,Animals ,Humans ,Immunology and Allergy ,Cell Proliferation ,Mice, Knockout ,Lymphokines ,Mice, Inbred BALB C ,Peripheral Tolerance ,Effector ,Chemistry ,Peripheral tolerance ,Cell Differentiation ,Cell biology ,Mice, Inbred C57BL ,030104 developmental biology ,medicine.anatomical_structure ,Cell culture ,Interleukin-2 ,Female ,Immunotherapy ,Signal Transduction - Abstract
IL-2 is critical for peripheral tolerance mediated by regulatory T (Treg) cells, which represent an obstacle for effective cancer immunotherapy. Although IL-2 is important for effector (E) T cell function, it has been hypothesized that therapies blocking IL-2 signals weaken Treg cell activity, promoting immune responses. This hypothesis has been partially tested using anti–IL-2 or anti–IL-2R Abs with antitumor effects that cannot be exclusively attributed to lack of IL-2 signaling in vivo. In this work, we pursued an alternative strategy to block IL-2 signaling in vivo, taking advantage of the trimeric structure of the IL-2R. We designed an IL-2 mutant that conserves the capacity to bind to the αβ-chains of the IL-2R but not to the γc-chain, thus having a reduced signaling capacity. We show our IL-2 mutein inhibits IL-2 Treg cell–dependent differentiation and expansion. Moreover, treatment with IL-2 mutein reduces Treg cell numbers and impairs tumor growth in mice. A mathematical model was used to better understand the effect of the mutein on Treg and E T cells, suggesting suitable strategies to improve its design. Our results show that it is enough to transiently inhibit IL-2 signaling to bias E and Treg cell balance in vivo toward immunity.
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- 2018
10. T follicular regulatory cells in mice and men
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Ana Raquel Maceiras, Ana Agua-Doce, Luis Graca, and Válter R. Fonseca
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0301 basic medicine ,Immunology ,Autoimmunity ,Thymus Gland ,T-Lymphocytes, Regulatory ,Mice ,03 medical and health sciences ,Interleukin 21 ,0302 clinical medicine ,T-Lymphocyte Subsets ,Animals ,Humans ,Immunology and Allergy ,Cytotoxic T cell ,IL-2 receptor ,Antigen-presenting cell ,Review Articles ,Autoantibodies ,CD40 ,biology ,ZAP70 ,Germinal center ,Germinal Center ,Natural killer T cell ,Cell biology ,Phenotype ,030104 developmental biology ,Immune System Diseases ,biology.protein ,Cytokines ,Biomarkers ,030215 immunology - Abstract
It has long been known that CD4 T cells are necessary to provide help to B cells, triggering a germinal centre (GC) reaction where affinity maturation and isotype switching occur. However, the nature of the dedicated CD4 helper T cells, known as T follicular helper (Tfh), was only recently described. Here, we review the biology and function of the recently described T follicular regulatory (Tfr) cells, another CD4 T-cell population also found within GCs but with regulatory function and characteristics. Tfr cells have been identified in mice and humans as simultaneously presenting characteristics of T follicular cells (namely CXCR5 expression) and regulatory T cells (including Foxp3 expression). These Tfr cells have been implicated in the regulation of the magnitude of the GC reaction, as well as in protection from immune-mediated pathology.
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- 2017
11. T Follicular Regulatory Cells Are Decreased in Patients With Established Treated Rheumatoid Arthritis With Active Disease: Comment on the Article by Liu et al
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João Eurico Fonseca, Vasco C. Romão, Luis Graca, and Ana Agua-Doce
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030203 arthritis & rheumatology ,0301 basic medicine ,Oncology ,medicine.medical_specialty ,business.industry ,Immunology ,medicine.disease ,T-Lymphocytes, Regulatory ,Arthritis, Rheumatoid ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Text mining ,Rheumatology ,Rheumatoid arthritis ,Internal medicine ,Follicular phase ,Active disease ,Humans ,Immunology and Allergy ,Medicine ,In patient ,business ,Medical science ,Autoantibodies - Published
- 2018
12. Dendritic Cells Expressing MyD88 Molecule Are Necessary and Sufficient for CpG-Mediated Inhibition of IgE Production In Vivo
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Ricardo Wesley Alberca-Custodio, Eliane Gomes, Luis Graca, Niels Olsen Saraiva Câmara, Fernanda Peixoto Barbosa Nunes, Luciana Mirotti, Raquel de Souza Vieira, Momtchilo Russo, and Rafael Ribeiro Almeida
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Allergy ,Ovalbumin ,medicine.medical_treatment ,Immunoglobulin E ,Article ,Mice ,Adjuvants, Immunologic ,In vivo ,medicine ,anaphylaxis ,Respiratory Hypersensitivity ,Animals ,Humans ,Alum adjuvant ,lcsh:QH301-705.5 ,Sensitization ,HIPERSENSIBILIDADE ,B-Lymphocytes ,biology ,Chemistry ,allergology ,TLR9 ,hemic and immune systems ,General Medicine ,Dendritic Cells ,medicine.disease ,allergy ,Disease Models, Animal ,medicine.anatomical_structure ,lcsh:Biology (General) ,CpG site ,IgG2c ,Gene Expression Regulation ,Oligodeoxyribonucleotides ,Immunology ,Myeloid Differentiation Factor 88 ,biology.protein ,Female ,IgE ,Antibody ,Adjuvant ,Anaphylaxis ,Signal Transduction - Abstract
Elevated levels of immunoglobulin E (IgE) are associated with allergies and other immunological disorders. Sensitization with alum adjuvant favours IgE production while CpG-ODN adjuvant, a synthetic toll-like receptor 9 (TLR9) agonist, inhibits it. The cellular mechanisms underlying in vivo TLR regulation of immunoglobulin production, specially IgE, are still controversial. Specifically, TLR-mediated IgE regulation in vivo is not yet known. In this study we showed that augmented levels of IgE induced by sensitizations to OVA with or without alum adjuvant or with OVA-pulsed dendritic cells (DCs) were inhibited by co-administration of CpG. Notably, CpG-mediated suppression of IgE production required MyD88-expression on DCs but not on B-cells. This finding contrasts with previous in vitro studies reporting regulation of IgE by a direct action of CpG on B cells via MyD88 pathway. In addition, we showed that CpG also inhibited IgE production in a MyD88-dependent manner when sensitization was performed with OVA-pulsed DCs. Finally, CpG signalling through MyD88 pathway was also necessary and sufficient to prevent anaphylactic antibody production involved in active cutaneous anaphylaxis.
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- 2019
13. T follicular helper cells and T follicular regulatory cells in rheumatic diseases
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Jun Deng, Yunbo Wei, Di Yu, Válter R. Fonseca, and Luis Graca
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biology ,business.industry ,Cell ,Autoantibody ,Autoimmunity ,T-Lymphocytes, Helper-Inducer ,medicine.disease_cause ,Phenotype ,T-Lymphocytes, Regulatory ,medicine.anatomical_structure ,Rheumatology ,Rheumatic Diseases ,Follicular phase ,Immunology ,biology.protein ,medicine ,Humans ,Antibody ,business ,Gene ,Function (biology) ,Autoantibodies - Abstract
As a hallmark of autoimmune rheumatic diseases, autoantibodies have been used in diagnosis for decades. However, the immunological mechanism underlying their generation has only become clear following the identification of T follicular helper (TFH) cells and T follicular regulatory (TFR) cells. TFH cells are instrumental in supporting antibody affinity maturation in germinal centre reactions and humoral memory formation, whereas TFR cells suppress TFH cell-mediated antibody responses. Evidence indicates that patients with autoimmune rheumatic diseases have increased numbers of TFH cells that can be hyperactive, and also potentially have altered numbers of TFR cells with reduced function, suggesting a conceivable dysregulation in the balance between TFH cells and TFR cells in these diseases. Therefore, by identifying the molecular mechanisms underlying the development and function of these cell populations, new opportunities have emerged to develop novel therapeutic targets. An increased knowledge of TFH cells and TFR cells has inspired, and hopefully will inspire more, approaches to reinstate the balance of these cells in the prevention and treatment of rheumatic diseases. T follicular helper cells and T follicular regulatory cells tightly control the production of (auto)antibodies by B cells. Understanding their phenotypes and how the function of these cells is dysregulated in rheumatic diseases will aid future therapeutic development.
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- 2019
14. Contribution of FoxP3(+) Tfr cells to overall human blood CXCR5(+) T cells
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Luis Graca and Válter R. Fonseca
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0301 basic medicine ,Receptors, CXCR5 ,Genotype ,T cell ,Immunology ,Biology ,medicine.disease_cause ,T-Lymphocytes, Regulatory ,CXCR5 ,Salivary Glands ,Autoimmunity ,Pathogenesis ,03 medical and health sciences ,0302 clinical medicine ,Follicular phase ,medicine ,Forkhead Box ,Immunology and Allergy ,Humans ,Letter to the Editor ,Human blood ,FOXP3 ,Forkhead Transcription Factors ,030104 developmental biology ,medicine.anatomical_structure ,Sjogren's Syndrome ,030215 immunology - Abstract
Summary The identification that T follicular helper (Tfh) cells is critical for the emergence of germinal centre responses prompted the study of CXCR5-expressing CD4+ T cell subsets in autoimmunity. However, circulating CXCR5-expressing T cells are heterogeneous by containing Forkhead box protein 3 (FoxP3)+ T follicular regulatory (Tfr) cells in addition to bona fide Tfh cells. Such heterogeneity may hamper the analysis of the contribution of specific follicular T cell subsets for autoimmune pathogenesis. Therefore, separate assessment of Tfh and Tfr populations offer greater opportunities for stratification of autoimmune patients, such as Sjögren’s syndrome patients.
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- 2019
15. Directed evolution of super-secreted variants from phage-displayed human Interleukin-2
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Jorge Fernandez de Cossio-Diaz, Yaima Tundidor, Marlies Becker, Annia Pérez-Riverón, Pedro A. Valiente, Kalet León, Tania Carmenate, Julio Felipe Santo-Tomás, Luis Graca, Gertrudis Rojas, Yaquelín Ortiz, and Stefan Dübel
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0301 basic medicine ,Agonist ,Interleukin 2 ,Phage display ,medicine.drug_class ,Cell Survival ,Recombinant Fusion Proteins ,lcsh:Medicine ,Antineoplastic Agents ,Receptors, Fc ,Protein Engineering ,Article ,Evolution, Molecular ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Animals ,Humans ,Secretion ,Receptor ,lcsh:Science ,Cell Proliferation ,Multidisciplinary ,Chemistry ,lcsh:R ,Protein engineering ,Directed evolution ,Fusion protein ,Cell biology ,Mice, Inbred C57BL ,030104 developmental biology ,Amino Acid Substitution ,Interleukin-2 ,lcsh:Q ,Cell Surface Display Techniques ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Selection from a phage display library derived from human Interleukin-2 (IL-2) yielded mutated variants with greatly enhanced display levels of the functional cytokine on filamentous phages. Introduction of a single amino acid replacement selected that way (K35E) increased the secretion levels of IL-2-containing fusion proteins from human transfected host cells up to 20-fold. Super-secreted (K35E) IL-2/Fc is biologically active in vitro and in vivo, has anti-tumor activity and exhibits a remarkable reduction in its aggregation propensity- the major manufacturability issue limiting IL-2 usefulness up to now. Improvement of secretion was also shown for a panel of IL-2-engineered variants with altered receptor binding properties, including a selective agonist and a super agonist that kept their unique properties. Our findings will improve developability of the growing family of IL-2-derived immunotherapeutic agents and could have a broader impact on the engineering of structurally related four-alpha-helix bundle cytokines.
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- 2019
16. T follicular regulatory (Tfr) cells: dissecting the complexity of Tfr‐cell compartments
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Válter R. Fonseca, F. N. Ribeiro, Luis Graca, and Repositório da Universidade de Lisboa
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0301 basic medicine ,Interleukin 2 ,Humoral responses ,T regulatory cells ,Immunology ,Population ,Cell ,Biology ,Adaptive Immunity ,Lymphocyte Activation ,T-Lymphocytes, Regulatory ,Affinity maturation ,03 medical and health sciences ,0302 clinical medicine ,Cell Movement ,medicine ,Immunology and Allergy ,Animals ,Humans ,education ,education.field_of_study ,B-Lymphocytes ,FOXP3 ,Germinal center ,Cell Differentiation ,Forkhead Transcription Factors ,T-Lymphocytes, Helper-Inducer ,Germinal Center ,Cell biology ,030104 developmental biology ,medicine.anatomical_structure ,Immunoglobulin class switching ,Foxp3 ,Humoral immunity ,T follicular helper cells ,Interleukin-2 ,T follicular regulatory cells ,030215 immunology ,medicine.drug - Abstract
© 2019 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd, Germinal centers (GC) have been known as key anatomic structures in humoral immunity, where isotype switching and affinity maturation occur. As a consequence, elucidation of GC regulation has potential implications for the understanding of autoantibody-mediated diseases. It is now accepted that different regulatory mechanisms coexist, including the action of a specialized population of Foxp3+ regulatory T cells with unique access to the B-cell follicle: the T follicular regulatory (Tfr) cells. Tfr cells develop through a multistep process requiring migration through different compartments of lymphoid tissues. This review discusses the ontogeny and physiology of Tfr cells, their distribution within distinct anatomic compartments, and their function. A greater understanding of Tfr biology and GC regulation is likely to lead to better stratification of patients with autoantibody-mediated diseases, and to the identification of novel therapeutic targets., Research funded by PTDC/IMI-IMU/7038/2014, and LISBOA-01-0145-FEDER-007391, projeto cofinanciado pelo FEDER através POR Lisboa 2020–Programa Operacional Regional de Lisboa, do PORTUGAL 2020, e pela Fundação para a Ciência e a Tecnologia.
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- 2019
17. Regulation of the Germinal Center Response
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Marisa Stebegg, Saumya D. Kumar, Alyssa Silva-Cayetano, Valter R. Fonseca, Michelle A. Linterman, Luis Graca, Linterman, Michelle [0000-0001-6047-1996], and Apollo - University of Cambridge Repository
- Subjects
lcsh:Immunologic diseases. Allergy ,0301 basic medicine ,Cell type ,Cellular differentiation ,B-cell receptor ,Immunology ,germinal center (GC) ,Autoimmunity ,Review ,Tfh cell ,03 medical and health sciences ,0302 clinical medicine ,Antigen ,medicine ,Immunology and Allergy ,Animals ,Humans ,Clonal Selection, Antigen-Mediated ,B cell ,B-Lymphocytes ,Tfr cell ,biology ,immuneregulation ,humoral responses ,Germinal center ,FOXP3 ,Cell Differentiation ,T-Lymphocytes, Helper-Inducer ,Germinal Center ,Lymphocyte Subsets ,Cell biology ,Immunity, Humoral ,030104 developmental biology ,medicine.anatomical_structure ,Self Tolerance ,Cellular Microenvironment ,biology.protein ,Antibody ,lcsh:RC581-607 ,030215 immunology - Abstract
The germinal center (GC) is a specialized microstructure that forms in secondary lymphoid tissues, producing long-lived antibody secreting plasma cells and memory B cells, which can provide protection against reinfection. Within the GC, B cells undergo somatic mutation of the genes encoding their B cell receptors which, following successful selection, can lead to the emergence of B cell clones that bind antigen with high affinity. However, this mutation process can also be dangerous, as it can create autoreactive clones that can cause autoimmunity. Because of this, regulation of GC reactions is critical to ensure high affinity antibody production and to enforce self-tolerance by avoiding emergence of autoreactive B cell clones. A productive GC response requires the collaboration of multiple cell types. The stromal cell network orchestrates GC cell dynamics by controlling antigen delivery and cell trafficking. T follicular helper (Tfh) cells provide specialized help to GC B cells through cognate T-B cell interactions while Foxp3+ T follicular regulatory (Tfr) cells are key mediators of GC regulation. However, regulation of GC responses is not a simple outcome of Tfh/Tfr balance, but also involves the contribution of other cell types to modulate the GC microenvironment and to avoid autoimmunity. Thus, the regulation of the GC is complex, and occurs at multiple levels. In this review we outline recent developments in the biology of cell subsets involved in the regulation of GC reactions, in both secondary lymphoid tissues, and Peyer's patches (PPs). We discuss the mechanisms which enable the generation of potent protective humoral immunity whilst GC-derived autoimmunity is avoided.
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- 2018
18. IL-9 Production by Nonconventional T helper Cells
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Silvia C P, Almeida and Luis, Graca
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Th2 Cells ,T-Lymphocyte Subsets ,Interleukin-9 ,Humans ,T-Lymphocytes, Helper-Inducer ,Th1 Cells ,Flow Cytometry - Abstract
IL-9 is a pro-inflammatory cytokine implicated in certain immune-mediated diseases where chronic or acute inflammation of the mucosa plays an important role. Although initially described as being produced by what was then thought to be Th2 cells, it was later described that specialized lymphocyte populations are involved in IL-9 production. In addition to the classical Th9 effector (subset of CD4+ T cells), IL-9 is also produced by nonconventional lymphocytes, namely invariant natural killer T (iNKT) cells and innate lymphoid cells (ILCs). The identification of IL-9-producing cells by flow cytometry and cytokine measurements are pivotal for assigning and defining functional cellular phenotypes. In this chapter we provide methods for the in vitro polarization of IL-9-producing nonconventional lymphocytes and the best conditions for the detection of IL-9 production by intracellular staining.
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- 2017
19. Poly(lactic acid)-based particulate systems are promising tools for immune modulation
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Eva Zupancic, Carina Peres, Vanessa Sainz, Ana I. Matos, Luis Graca, Joana M. Silva, Helena F. Florindo, Véronique Préat, João Conniot, and Rogério Gaspar
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0301 basic medicine ,Materials science ,Polyesters ,medicine.medical_treatment ,Biomedical Engineering ,Nanotechnology ,02 engineering and technology ,Biochemistry ,Immunomodulation ,Biomaterials ,03 medical and health sciences ,chemistry.chemical_compound ,Immune system ,Antigen ,medicine ,Animals ,Humans ,Molecular Biology ,Vaccines ,Immunity ,General Medicine ,Immunotherapy ,021001 nanoscience & nanotechnology ,Controlled release ,3. Good health ,Lactic acid ,Vaccination ,PLGA ,030104 developmental biology ,chemistry ,Nanoparticles ,0210 nano-technology ,Adjuvant ,Biotechnology - Abstract
Poly(lactic acid) (PLA) is one of the most successful and versatile polymers explored for controlled delivery of bioactive molecules. Its attractive properties of biodegradability and biocompatibility in vivo have contributed in a meaningful way to the approval of different products by the FDA and EMA for a wide range of biomedical and pharmaceutical applications, in the past two decades. This polymer has been widely used for the preparation of particles as delivery systems of several therapeutic molecules, including vaccines. These PLA vaccine carriers have shown to induce a sustained and targeted release of different bacterial, viral and tumor-associated antigens and adjuvants in vivo, triggering distinct immune responses. The present review intends to highlight and discuss the major advantages of PLA as a promising polymer for the development of potent vaccine delivery systems against pathogens and cancer. It aims to provide a critical discussion based on preclinical data to better understand the major effect of PLA-based carrier properties on their interaction with immune cells and thus their role in the modulation of host immunity. Statement of Significance During the last decades, vaccination has had a great impact on global health with the control of many severe diseases. Polymeric nanosystems have emerged as promising strategies to stabilize vaccine antigens, promoting their controlled release to phagocytic cells, thus avoiding the need for multiple administrations. One of the most promising polymers are the aliphatic polyesters, which include the poly(lactic acid). This is a highly versatile biodegradable and biocompatible polymer. Products containing this polymer have already been approved for all food and some biomedical applications. Despite all favorable characteristics presented above, PLA has been less intensively discussed than other polymers, such as its copolymer PLGA, including regarding its application in vaccination and particularly in tumor immunotherapy. The present review discusses the major advantages of poly(lactic acid) for the development of potent vaccine delivery systems, providing a critical view on the main properties that determine their effect on the modulation of immune cells.
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- 2017
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20. Reply
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Ana Agua-Doce, João Eurico Fonseca, Válter R. Fonseca, Luis Graca, and Vasco C. Romão
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0301 basic medicine ,Oncology ,medicine.medical_specialty ,business.industry ,T cell ,Immunology ,T-Lymphocytes, Helper-Inducer ,Stratification (mathematics) ,03 medical and health sciences ,Sjogren's Syndrome ,030104 developmental biology ,medicine.anatomical_structure ,Rheumatology ,Internal medicine ,Follicular phase ,Humans ,Immunology and Allergy ,Medicine ,Sjogren s ,business ,Biomarkers - Published
- 2018
21. BAFF and TACI Gene Expression Are Increased in Patients with Untreated Very Early Rheumatoid Arthritis
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João Eurico Fonseca, João Madruga Dias, Joaquim Polido-Pereira, Raquel Campanilho-Marques, Ana Filipa Mourão, Rita A Moura, José Alberto Pereira da Silva, C Resende, Helena Canhão, Ana M. Rodrigues, Márcio Navalho, Luis Graca, and Repositório da Universidade de Lisboa
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Male ,Chemokine ,Time Factors ,B Cells ,Transmembrane Activator and CAML Interactor Protein ,Arthritis, Rheumatoid ,0302 clinical medicine ,B-Cell Activating Factor ,Homeostasis ,Immunology and Allergy ,Receptor ,B-Lymphocytes ,0303 health sciences ,biology ,Messenger RNA ,Middle Aged ,medicine.anatomical_structure ,Disease Progression ,BAFF ,Female ,Tumor necrosis factor alpha ,Adult ,medicine.medical_specialty ,Cell Survival ,Immunology ,Rheumatoid Arthritis ,Peripheral blood mononuclear cell ,03 medical and health sciences ,Rheumatology ,Internal medicine ,medicine ,Humans ,RNA, Messenger ,B-cell activating factor ,BAFF receptor ,B cell ,Aged ,030304 developmental biology ,030203 arthritis & rheumatology ,business.industry ,TACI ,B-Cell Maturation Antigen ,Endocrinology ,Gene Expression Regulation ,Case-Control Studies ,biology.protein ,business ,Biomarkers - Abstract
The Journal of Rheumatology Copyright © 2013. All rights reserved., Objective: B cells play important roles in rheumatoid arthritis (RA). Given the beneficial effect of B cell depletion therapy in RA as well as the observed alterations in B cell subpopulations in this disease, we evaluated whether changes in the expression of genes related to B cell survival and activation were already present in patients with untreated very early RA (VERA; < 6 weeks of disease duration). Methods: The expression of a group of B cell-related activation and survival genes was quantified in peripheral blood mononuclear cells from patients with VERA by real-time PCR and compared with untreated early RA (< 1 year), established treated RA, and other untreated early arthritis conditions. Serum B cell-activating factor belonging to the tumor necrosis factor family (BAFF) was quantified by ELISA. Results: BAFF gene expression and serum levels were highest in patients with VERA. The expression of BAFF receptor (BAFF-R) increased with disease progression, while transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) was elevated since the first weeks of RA onset. Paired box 5 gene expression was also increased at all RA stages. Chemokine (C-X-C motif) receptor 5 was elevated only in established RA. No differences were observed in B cell maturation antigen, activation-induced cytidine deaminase, B lymphocyte-induced maturation protein, and B cell lymphoma 2 expression. Conclusion: Disturbances in the expression of B cell-related activation and survival genes, particularly BAFF and TACI, occur from the onset of RA and precede changes in BAFF-R. These alterations can lead to the development of autoreactive B cells from the first weeks of RA onset., Supported by a grant from Sociedade Portuguesa de Reumatologia/Schering-Plough 2005. RAM was funded by a fellowship from Fundação para a Ciência e a Tecnologia (SFRH/BD/30247/2006).
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- 2013
22. Umbilical cord tissue-derived mesenchymal stromal cells maintain immunomodulatory and angiogenic potencies after cryopreservation and subsequent thawing
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Pedro E. Cruz, Mariana Filipe, Maria Manuela Gaspar, Ana Agua-Doce, Augusto Ministro, Joana P. Miranda, Sandra Simões, Luis Graca, Mariana Teixeira, Jorge M. Santos, Ana Santos Pereira, Manuela Carvalheiro, Rita N. Bárcia, Helder Cruz, and Susana Constantino Rosa Santos
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0301 basic medicine ,Male ,Cancer Research ,Stromal cell ,Angiogenesis ,Immunology ,Population ,Neovascularization, Physiologic ,Biology ,Mesenchymal Stem Cell Transplantation ,Cryopreservation ,Immunophenotyping ,Umbilical Cord ,Immunomodulation ,03 medical and health sciences ,Mice ,In vivo ,Freezing ,Immunology and Allergy ,Animals ,Humans ,Rats, Wistar ,education ,Genetics (clinical) ,Cells, Cultured ,Transplantation ,education.field_of_study ,Mesenchymal stem cell ,Cell Differentiation ,Mesenchymal Stem Cells ,Cell Biology ,Flow Cytometry ,Rats ,Mice, Inbred C57BL ,030104 developmental biology ,Oncology ,Cancer research ,CD146 ,Human umbilical vein endothelial cell ,Female - Abstract
Background aims The effect of cryopreservation on mesenchymal stromal cell (MSC) therapeutic properties has become highly controversial. However, data thus far have indiscriminately involved the assessment of different types of MSCs with distinct production processes. This study assumed that MSC-based products are affected differently depending on the tissue source and manufacturing process and analyzed the effect of cryopreservation on a specific population of umbilical cord tissue–derived MSCs (UC-MSCs), UCX ® . Methods Cell phenotype was assessed by flow cytometry through the evaluation of the expression of relevant surface markers such as CD14, CD19, CD31, CD34, CD44, CD45, CD90, CD105, CD146, CD200, CD273, CD274 and HLA-DR. Immunomodulatory activity was analyzed in vitro through the ability to inhibit activated T cells and in vivo by the ability to reverse the signs of inflammation in an adjuvant-induced arthritis (AIA) model. Angiogenic potential was evaluated in vitro using a human umbilical vein endothelial cell–based angiogenesis assay, and in vivo using a mouse model for hindlimb ischemia. Results Phenotype and immunomodulatory and angiogenic potencies of this specific UC-MSC population were not impaired by cryopreservation and subsequent thawing, both in vitro and in vivo . Discussion This study suggests that potency impairment related to cryopreservation in a given tissue source can be avoided by the production process. The results have positive implications for the development of advanced-therapy medicinal products.
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- 2016
23. Serial analysis of gene expression provides new insights into regulatory T cells
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Luis Graca, Elizabeth Adams, Stephen P. Cobbold, and Herman Waldmann
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Regulation of gene expression ,Gene Expression Profiling ,T-Lymphocytes ,Immunology ,Peripheral tolerance ,Computational biology ,Th1 Cells ,Biology ,Immune tolerance ,TCIRG1 ,Transplantation ,Gene expression profiling ,Gene Expression Regulation ,Immune Tolerance ,Animals ,Humans ,Immunology and Allergy ,IL-2 receptor ,Serial analysis of gene expression ,Biomarkers - Abstract
It is now possible to induce donor-specific transplantation tolerance in adult rodents using a number of therapeutic strategies. Such peripheral tolerance is maintained by regulatory CD4+ T cells, not only in transplantation models, but also in autoimmunity. Differential gene expression analyses have been used to identify potential new markers for regulatory T cells, aiming to reveal new insights into their mechanisms of action, and to find novel targets for therapeutic manipulation of the immune system.
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- 2016
24. Monoclonal anti-CD8 therapy induces disease amelioration in the K/BxN mouse model of spontaneous chronic polyarthritis
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Paulo Rodrigues-Santos, Helena Carvalheiro, Lina Carvalho, Bruno Raposo, Ana Agua-Doce, José António Pereira da Silva, Luis Graca, M. Margarida Souto-Carneiro, and Repositório da Universidade de Lisboa
- Subjects
Immunoconjugates ,Artrite Experimental ,CD8 Antigens ,T-Lymphocytes ,medicine.medical_treatment ,T cell ,Immunology ,Antigénio CD8 ,Arthritis ,Mice, Transgenic ,CD8-Positive T-Lymphocytes ,Antigens, CD8 ,Proinflammatory cytokine ,Mice ,03 medical and health sciences ,0302 clinical medicine ,Anticorpos Monoclonais ,Rheumatology ,Mice, Inbred NOD ,medicine ,Animals ,Humans ,Immunology and Allergy ,Pharmacology (medical) ,Antibodies, monoclonal ,030304 developmental biology ,0303 health sciences ,Synovitis ,biology ,business.industry ,medicine.disease ,Arthritis, Experimental ,3. Good health ,Mice, Inbred C57BL ,Granzyme B ,Cytokine ,medicine.anatomical_structure ,Granzyme ,biology.protein ,Tumor necrosis factor alpha ,business ,CD8 ,030215 immunology - Abstract
© 2010, American College of Rheumatology, Objective. CD8+ T cells are part of the T cell pool infiltrating the synovium in rheumatoid arthritis (RA). However, their role in the pathogenesis of RA has not been fully delineated. Using the K/BxN mouse model of spontaneous chronic arthritis, which shares many similarities with RA, we studied the potential of CD8 T cell depletion with monoclonal antibodies (mAb) to stop and reverse the progression of experimental arthritis. Methods. CD8+ T cells from the blood and articular infiltrate of K/BxN mice were characterized for cell surface phenotypic markers and for cytokine production. Additionally, mice were treated with specific anti-CD8 mAb (YTS105 and YTS169.4), with and without thymectomy. Results. CD8+ T cells from the peripheral blood and joints of K/BxN mice were mainly CD69+ and CD62L-CD27+ T cells expressing proinflammatory cytokines (interferon-γ [IFNγ], tumor necrosis factor α [TNFα], interleukin-17a [IL-17A], and IL-4), and granzyme B. In mice receiving anti-CD8 mAb, the arthritis score improved 5 days after treatment. Recovery of the CD8+ T cells was associated with a new increase in the arthritis score after 20 days. In thymectomized and anti-CD8 Ab–treated mice, the arthritis score improved permanently. Histologic analysis showed an absence of inflammatory infiltrate in the anti-CD8 mAb–treated mice. In anti-CD8 mAb–treated mice, the serologic levels of TNFα, IFNγ, IL-6, and IL-5 normalized. The levels of the disease-related anti–glucose-6-phosphate isomerase antibodies did not change. Conclusion. These results indicate that synovial activated effector CD8 T cells locally synthesize proinflammatory cytokines (IFNγ, TNFα, IL-17, IL-6) and granzyme B in the arthritic joint, thus playing a pivotal role in maintaining chronic synovitis in the K/BxN mouse model of arthritis., Mr. Raposo’s work was supported by the Instituto do Emprego e Formação Profissional (grant 266/EP/2006) and the Fundação para a Ciência e Tecnologia (grant SFRH/BD/40658/2007). Ms Carvalheiro’s work was supported by the Fundação para a Ciência e Tecnologia (grant SFRH/BD/60467/2009). Dr. Graça’s work was supported by the Fundação para a Ciência e Tecnologia (grant POCI/SAU-MMO/55974/2004). Dr. Souto-Carneiro’s work was supported by a Marie Curie Intra-European Fellowship (LIF-025885) and a EULAR Young Investigator Award.
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- 2010
25. Transplantation tolerance: context matters
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Luis, Graca
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Animals ,Antibodies, Monoclonal ,Humans ,Apoptosis ,Transplantation Tolerance - Abstract
Costimulation blockade has been one of the most studied strategies to achieve immune tolerance, particularly in transplantation. Yet, in spite of the robust nature of the tolerance-inducing potential of costimulation blockade, a comprehensive understanding of the molecular and cellular mechanisms underlying tolerance induction is still missing. Nevertheless, progress has been continuously made. In this issue of the European Journal of Immunology, Chai et al. [Eur. J. Immunol. 2015. 45: 2017-2027] show that transplantation tolerance induced with an anti-CD154 monoclonal antibody relies on the coexistence of several tolerogenic mechanisms rather than one simple regulatory mechanism. These observations highlight the importance of concerted actions involving multiple pathways, namely apoptosis, acquisition of regulatory cells, or inhibition of proliferation, all of which contribute to the induction and maintenance of robust immune tolerance. A better understanding of these distinct tolerogenic pathways may lead to the development of better tolerance-inducing therapeutics.
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- 2015
26. IL-9 expression by invariant NKT cells is not imprinted during thymic development
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Luis Graca, Henrique Veiga-Fernandes, Ana Agua-Doce, Catarina F. Almeida, Marta Monteiro, Diogo Fonseca-Pereira, and Repositório da Universidade de Lisboa
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Adoptive cell transfer ,Immunology ,Population ,Thymus Gland ,Biology ,Proinflammatory cytokine ,03 medical and health sciences ,Mice ,0302 clinical medicine ,Transforming Growth Factor beta ,BATF ,Immunology and Allergy ,Animals ,Antigens, Ly ,Humans ,Interleukin 9 ,Mast Cells ,education ,Lung ,Interleukin 4 ,Cells, Cultured ,030304 developmental biology ,Inflammation ,Mice, Knockout ,0303 health sciences ,education.field_of_study ,Mice, Inbred BALB C ,Pyroglyphidae ,Interleukin-9 ,Pneumonia ,Natural killer T cell ,Adoptive Transfer ,Neuropilin-1 ,Mice, Inbred C57BL ,Basic-Leucine Zipper Transcription Factors ,CD4 Antigens ,Interferon Regulatory Factors ,Leukocytes, Mononuclear ,Natural Killer T-Cells ,Interleukin-4 ,Cell activation ,030215 immunology ,Granulocytes ,NK Cell Lectin-Like Receptor Subfamily B - Abstract
Copyright © 2015 by The American Association of Immunologists, Inc. All rights reserved, Invariant NKT (iNKT) cell thymic development can lead to distinct committed effector lineages, namely NKT1, NKT2, and NKT17. However, following identification of IL-9-producing iNKT cells involved in mucosal inflammation, their development remains unaddressed. In this study, we report that although thymic iNKT cells from naive mice do not express IL-9, iNKT cell activation in the presence of TGF-β and IL-4 induces IL-9 secretion in murine and human iNKT cells. Acquisition of IL-9 production was observed in different iNKT subsets defined by CD4, NK1.1, and neuropilin-1, indicating that distinct functional subpopulations are receptive to IL-9 polarization. Transcription factor expression kinetics suggest that regulatory mechanisms of IL-9 expression are shared by iNKT and CD4 T cells, with Irf4 and Batf deficiency deeply affecting IL-9 production. Importantly, adoptive transfer of an enriched IL-9(+) iNKT cell population leads to exacerbated allergic inflammation in the airways upon intranasal immunization with house dust mite, confirming the ability of IL-9-producing iNKT cells to mediate proinflammatory effects in vivo, as previously reported. Taken together, our data show that peripheral iNKT cells retain the capacity of shaping their function in response to environmental cues, namely TGF-β and IL-4, adopting an IL-9-producing NKT cell phenotype able to mediate proinflammatory effects in vivo, namely granulocyte and mast cell recruitment to the lungs., This work was supported by Fundação Para a Ciência e Tecnologia, Portugal Grants PTDC/SAU-TOX/114424/2009 and HMSP-ICT/0034/2013 and the Novo Nordisk/European Foundation for the Study of Diabetes (to L.G.), as well as by grants from the Fundação Para a Ciência e Tecnologia, Portugal, the European Molecular Biology Organization, the European Research Council, and the U.S. National Blood Foundation (to H.V.-F.). A.A.-D., C.F.A., D.F.-P., and M.M. were supported by fellowships from the Fundação Para a Ciência e Tecnologia, Portugal.
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- 2015
27. Immune privilege induced by regulatory T cells in transplantation tolerance
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Kathleen F. Nolan, Herman Waldmann, Paul J. Fairchild, Elizabeth Adams, Stephen F. Yates, Stephen P. Cobbold, Nathan J. Robertson, Alison M. Paterson, Stephen R. Daley, and Luis Graca
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Graft Rejection ,medicine.medical_treatment ,Immunology ,Immunosuppression ,Inflammation ,Dendritic cell ,Biology ,T-Lymphocytes, Regulatory ,Immune tolerance ,Transplantation ,Immune system ,Immune privilege ,medicine ,Animals ,Humans ,Indoleamine-Pyrrole 2,3,-Dioxygenase ,Immunology and Allergy ,Transplantation Tolerance ,medicine.symptom ,Antigen-presenting cell - Abstract
Immune privilege was originally believed to be associated with particular organs, such as the testes, brain, the anterior chamber of the eye, and the placenta, which need to be protected from any excessive inflammatory activity. It is now becoming clear, however, that immune privilege can be acquired locally in many different tissues in response to inflammation, but particularly due to the action of regulatory T cells (Tregs) induced by the deliberate therapeutic manipulation of the immune system toward tolerance. In this review, we consider the interplay between Tregs, dendritic cells, and the graft itself and the resulting local protective mechanisms that are coordinated to maintain the tolerant state. We discuss how both anti-inflammatory cytokines and negative costimulatory interactions can elicit a number of interrelated mechanisms to regulate both T-cell and antigen-presenting cell activity, for example, by catabolism of the amino acids tryptophan and arginine and the induction of hemoxygenase and carbon monoxide. The induction of local immune privilege has implications for the design of therapeutic regimens and the monitoring of the tolerant status of patients being weaned off immunosuppression.
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- 2006
28. The blind-spot of regulatory T cells
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Luis Graca, Bruno Silva-Santos, Antonio Coutinho, and Repositório da Universidade de Lisboa
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Immunology ,Population ,Cell Culture Techniques ,Autoimmunity ,chemical and pharmacologic phenomena ,Biology ,Lymphocyte Activation ,medicine.disease_cause ,T-Lymphocytes, Regulatory ,Mice ,Negative selection ,Immune system ,Immune Tolerance ,medicine ,Animals ,Humans ,Immunology and Allergy ,IL-2 receptor ,education ,Thymic selection ,education.field_of_study ,FOXP3 ,hemic and immune systems ,Regulatory T cells ,Dendritic Cells ,Dendritic cell ,medicine.disease ,Transplant rejection ,Tolerance - Abstract
Copyright © 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim., CD4+ CD25+ Foxp3+ regulatory T cells (Treg) are natural suppressors of autoimmunity but they can also dampen the effective clearance of infectious organisms. These cells have the potential to be exploited to prevent transplant rejection and to treat autoimmune disease. A paper in this issue of the European Journal of Immunology details a method to selectively expand antigen-specific Treg from a polyclonal Treg population, by using a specific dendritic cell (DC) subset. Furthermore, the authors show that such Treg can be used to prevent experimental type I diabetes; however, as Treg are positively selected by thymic epithelial cells (TEC) on the basis of self-reactivity, they would systematically suppress protective immune responses unless their repertoire is devoid of recognition towards peripheral antigen-presenting cells. This may be achieved by negative selection of developing Treg on thymic DC, thus creating a 'blind-spot' corresponding to DC-self-antigens in the mature Treg repertoire. Therefore, therapeutic use of DC subsets for the expansion of rare Treg populations should take into account this blind-spot, as peptides that are not accessible to thymic DC may be significantly more effective for the expansion of Treg.
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- 2006
29. Towards an advanced therapy medicinal product based on mesenchymal stromal cells isolated from the umbilical cord tissue: quality and safety data
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Ana Agua-Doce, Joana Almeida, S. Almeida, Luis Graca, Kurt E.J. Dittmar, Werner Lindenmaier, Mari Gilljam, Birgitta Stellan, Jorge M. Santos, Helder Cruz, Evren Alici, Pedro E. Cruz, Mariana Vargas Teixeira de Almeida, Alexandre Varela, José Paulo Martins, Mariana Filipe, Rita N. Bárcia, and Susanne Pohl
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Quality Control ,Population ,Medicine (miscellaneous) ,Biology ,Mesenchymal Stem Cell Transplantation ,Biochemistry, Genetics and Molecular Biology (miscellaneous) ,Cryopreservation ,Flow cytometry ,Umbilical Cord ,Cell therapy ,chemistry.chemical_compound ,medicine ,Humans ,education ,Cells, Cultured ,education.field_of_study ,Mesenchymal Stromal Cells ,medicine.diagnostic_test ,Research ,Mesenchymal stem cell ,Mesenchymal Stem Cells ,Cell Biology ,Stem Cell Research ,Cell biology ,chemistry ,Cell culture ,Immunology ,Tissue and Organ Harvesting ,Molecular Medicine ,Stem cell ,ATMP - Abstract
Introduction Standardization of mesenchymal stromal cells (MSCs) manufacturing is urgently needed to enable translational activities and ultimately facilitate comparison of clinical trial results. In this work we describe the adaptation of a proprietary method for isolation of a specific umbilical cord tissue-derived population of MSCs, herein designated by its registered trademark as UCX®, towards the production of an advanced therapy medicinal product (ATMP). Methods The adaptation focused on different stages of production, from cell isolation steps to cell culturing and cryopreservation. The origin and quality of materials and reagents were considered and steps for avoiding microbiological and endotoxin contamination of the final cell product were implemented. Cell isolation efficiency, MSCs surface markers and genetic profiles, originating from the use of different medium supplements, were compared. The ATMP-compliant UCX® product was also cryopreserved avoiding the use of dimethyl sulfoxide, an added benefit for the use of these cells as an ATMP. Cells were analyzed for expansion capacity and longevity. The final cell product was further characterized by flow cytometry, differentiation potential, and tested for contaminants at various passages. Finally, genetic stability and immune properties were also analyzed. Results The isolation efficiency of UCX® was not affected by the introduction of clinical grade enzymes. Furthermore, isolation efficiencies and phenotype analyses revealed advantages in the use of human serum in cell culture as opposed to human platelet lysate. Initial decontamination of the tissue followed by the use of mycoplasma- and endotoxin-free materials and reagents in cell isolation and subsequent culture, enabled the removal of antibiotics during cell expansion. UCX®-ATMP maintained a significant expansion potential of 2.5 population doublings per week up to passage 15 (P15). They were also efficiently cryopreserved in a DMSO-free cryoprotectant medium with approximately 100% recovery and 98% viability post-thaw. Additionally, UCX®-ATMP were genetically stable upon expansion (up to P15) and maintained their immunomodulatory properties. Conclusions We have successfully adapted a method to consistently isolate, expand and cryopreserve a well-characterized population of human umbilical cord tissue-derived MSCs (UCX®), in order to obtain a cell product that is compliant with cell therapy. Here, we present quality and safety data that support the use of the UCX® as an ATMP, according to existing international guidelines.
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- 2013
30. Cytokine pattern in very early rheumatoid arthritis favours B-cell activation and survival
- Author
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Helena Canhão, H S Rosário, Ana Filipa Mourão, E Vieira de Sousa, Rita Cascão, Joaquim Polido-Pereira, Luis Graca, I.P. Perpétuo, M. Margarida Souto-Carneiro, Rita A Moura, Ana M. Rodrigues, M Viana Queiroz, João Eurico Fonseca, and Repositório da Universidade de Lisboa
- Subjects
Male ,Time Factors ,medicine.medical_treatment ,Statistics as Topic ,Arthritis ,Disease ,030204 cardiovascular system & hematology ,Lymphocyte Activation ,Arthritis, Rheumatoid ,Interleukin 21 ,0302 clinical medicine ,hemic and lymphatic diseases ,Synovial Fluid ,Pharmacology (medical) ,APRIL ,VERA ,B-cell activation ,Medicine(all) ,0303 health sciences ,B-Lymphocytes ,General Medicine ,Middle Aged ,3. Good health ,Cytokine ,030220 oncology & carcinogenesis ,Rheumatoid arthritis ,BAFF ,Cytokines ,Polyarthritis ,Female ,musculoskeletal diseases ,Adult ,medicine.medical_specialty ,Tumor Necrosis Factor Ligand Superfamily Member 13 ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Immune system ,Rheumatology ,Internal medicine ,medicine ,Humans ,B-cell activating factor ,Interleukin 4 ,030304 developmental biology ,030203 arthritis & rheumatology ,B cells ,Biochemistry, Genetics and Molecular Biology(all) ,business.industry ,Autoantibody ,Synovial fluid ,Early rheumatoid arthritis ,medicine.disease ,Endocrinology ,Poster Presentation ,Immunology ,business - Abstract
© The Author 2010. Published by Oxford University Press on behalf of the British Society for Rheumatology., Objectives. B cells play an important role in the perpetuation of RA, particularly as autoantibody-producing cells. The ICs that further develop deposit in the joints and aggravate the inflammatory process. However, B-cell contribution in the very early stage of the disease remains unknown. The main goal of this work was to determine the concentration of cytokines potentially relevant for B-cell activation in serum from very early polyarthritis patients, with, Sociedade Portuguesa de Reumatologia/Schering-Plough 2005. R.A.M. and R.C. were funded by Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/30247/2006 and SFRH/BD/40513/2007, respectively. M.M.S.-C. was funded by Marie Curie Intra-European Fellowship PERG-2008-239422 and an EULAR Young Investigator Award.
- Published
- 2010
31. Mechanisms of tolerance and allergic sensitization in the airways and the lungs
- Author
-
Juan J. Lafaille, Luis Graca, Maria A Curotto de Lafaille, and Repositório da Universidade de Lisboa
- Subjects
Allergy ,Immunology ,Respiratory mucosa ,Inflammation ,Article ,Immune tolerance ,Airborne allergen ,Allergic sensitization ,Antigen ,Hypersensitivity ,Immune Tolerance ,medicine ,Animals ,Humans ,Immunology and Allergy ,Lung ,business.industry ,food and beverages ,FOXP3 ,Allergens ,Acquired immune system ,medicine.disease ,T-lymphocytes, regulatory ,Asthma ,medicine.symptom ,business - Abstract
© 2010 Elsevier Ltd. All rights reserved, The respiratory mucosa is constantly exposed to non-infectious substances that have the potential of triggering inflammation. While many particles are excluded, soluble molecules can reach the epithelium surface, where they can be uptaken by dendritic cells and stimulate an adaptive immune response. Most mucosal responses result in tolerance to subsequent antigen encounters, which is mediated by Foxp3(+) regulatory T cells. Genetic and environmental factors, added to the ability of certain allergens to induce innate responses, can predispose to allergic sensitization. In this review we discuss recent advances in the understanding of the mechanisms of tolerance and allergic sensitization to airborne allergens.
- Published
- 2010
32. Alterations on peripheral blood B-cell subpopulations in very early arthritis patients
- Author
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Luis Graca, João Eurico Fonseca, Joana Caetano-Lopes, Elsa Sousa, Helena Canhão, Patrícia Aparecida Pimenta Pereira, Rita A Moura, Ana Filipa Mourão, Queiroz Mv, Ana M. Rodrigues, M. Margarida Souto-Carneiro, Pamela Weinmann, and Repositório da Universidade de Lisboa
- Subjects
Adult ,Male ,medicine.medical_specialty ,Time Factors ,B-Lymphocyte Subsets ,Arthritis ,Autoimmunity ,medicine.disease_cause ,Young Adult ,Rheumatology ,Adrenal Cortex Hormones ,Internal medicine ,Humans ,Medicine ,Corticosteroids ,Pharmacology (medical) ,Lymphocyte Count ,Rheumatoid arthritis ,B cell ,Aged ,B cells ,Blood Cells ,business.industry ,Middle Aged ,Flow Cytometry ,medicine.disease ,Peripheral blood ,medicine.anatomical_structure ,Methotrexate ,Case-Control Studies ,Immunology ,Female ,Polyarthritis ,business ,Early arthritis - Abstract
©The Author 2010. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved., Objective. To characterize circulating B-cell subpopulations of arthritis patients with, This work was supported by a grant from Sociedade Portuguesa de Reumatologia/Schering- Plough 2005. R.A.M. was funded by Fundação para a Ciência e Tecnologia (FCT) SFRH/BD/30247/2006, and M.M.S.-C. by Marie Curie Intra-European Fellowship LIF-025885 and a EULAR Young Investigator Award.
- Published
- 2010
33. Haemophilia care in children--benefits of early prophylaxis for inhibitor prevention
- Author
-
Elena Santagostino, G. Auerswald, Luis Graca, and Maria Elisa Mancuso
- Subjects
medicine.medical_specialty ,Laboratory monitoring ,Haemophilia A ,Haemophilia ,Hemophilia A ,Drug Administration Schedule ,Immune system ,Hemarthrosis ,medicine ,Immune Tolerance ,Humans ,Intensive care medicine ,Child ,Genetics (clinical) ,Haemophilic arthropathy ,Factor VIII ,Blood Coagulation Factor Inhibitors ,business.industry ,Coagulants ,Infant, Newborn ,Infant ,Hematology ,General Medicine ,medicine.disease ,Antibody production ,Regimen ,Child, Preschool ,Immunology ,Complication ,business - Abstract
Summary. Haemophilia therapy is aimed at treating and preventing bleeding episodes and related complications and clinical studies have shown that regular prophylaxis, started at an early age, is able to reduce physical impairment from haemophilic arthropathy. Today, the development of anti-Factor VIII (FVIII) inhibitors is the most serious treatment-related complication of haemophilia therapy and a number of genetic and environmental risk factors have been identified in the past years. Clinical data show that early start of prophylaxis and the avoidance of intensive treatment periods may protect patients from inhibitor development. The mechanisms are not completely understood; yet, recent experimental data suggest that pro-inflammatory or ‘danger signals’ may be involved in inducing tolerance vs. an effector immune response. So, exposure to a factor concentrate by itself may not be enough to trigger an immune response, while an intensive exposure to FVIII in the presence of such ‘danger signals’ can activate antigen-presenting cells, up-regulating co-stimulatory signals for T lymphocytes and ultimately enhancing antibody production. The ‘optimal’ regimen for primary prophylaxis is still not identified and barriers to prophylaxis implementation remain relevant. Key issues include the optimal age at prophylaxis onset, the optimal dosage/schedule, the proper clinical and laboratory monitoring and patients’ compliance. Practical approaches to early prophylaxis as implemented in the haemophilia centres in Milan and Bremen are discussed in this respect.
- Published
- 2009
34. CTLA4Ig and the therapeutic potential of T cell co-stimulation blockade
- Author
-
Luis, Graca
- Subjects
Abatacept ,Arthritis, Rheumatoid ,Immunoconjugates ,Antirheumatic Agents ,T-Lymphocytes ,Cytokines ,Humans - Abstract
It is now generally accepted that CD4 T cells are critical players in the initiation of adaptive immune responses by contributing to the terminal differentiation of effector B cells or CD8+ T cells. It is therefore not surprising that CD4+ T cell activation is tightly controlled through the concerted action of a large number of molecular interactions. Activation requires not only the recognition of the appropriate antigen within a MHC molecule by the T cell receptor TCR but also the delivery of co-stimulatory signals by the antigen presenting cell APC . As a consequence therapeutic modulation of co-stimulatory molecules for instance with CTLA4Ig can lead to interference with T cell activation and consequently abrogation of pro-inflammatory manifestations mediated by cell types influenced by CD4+ T cells such as B cells CD8+ T cells or macrophages. This type of observations provided the rationale for the use of co-stimulatory blockade in autoimmunity and other immunopathology characterized by inappropriate immune activation such as rheumatoid arthritis RA . Several studies have also suggested that besides the non-specific anti-inflammatory effects co-stimulation blockade may in certain conditions promote the induction of long term immune tolerance.
- Published
- 2008
35. Regulatory T cell maintenance of dominant tolerance: induction of tissue self-defense?
- Author
-
Joana Duarte, Miguel P. Soares, Ana Agua-Doce, Vanessa G. Oliveira, and Luis Graca
- Subjects
Transplantation ,Regulatory T cell ,Immunology ,Models, Immunological ,Tryptophan ,Biology ,medicine.disease_cause ,medicine.disease ,T-Lymphocytes, Regulatory ,Autoimmunity ,Transplant rejection ,Immune tolerance ,Tolerance induction ,medicine.anatomical_structure ,Immune privilege ,Transplantation Immunology ,medicine ,Immune Tolerance ,Immunology and Allergy ,Animals ,Humans ,IL-2 receptor ,Gene ,Heme Oxygenase-1 - Abstract
In the last decade there has been an increasing interest for the action of regulatory T cells (Treg) in preventing transplant rejection, autoimmunity and other inflammatory diseases and in maintaining dominant tolerance. It is becoming clear that such regulatory function does not rely simply on direct inhibition of "aggressive" T cells. In fact, several studies suggest that Treg cells may induce changes in the target tissue, promoting a state of "immune privilege" where protective genes such as heme oxygenase-1 (HO-1) and indolamine 2,3 dioxygenase (IDO) may have a critical role.
- Published
- 2006
36. Regulatory T cells in transplantation
- Author
-
Stephen P. Cobbold, Herman Waldmann, Luis Graca, Elizabeth Adams, Tse Ching Chen, Paul J. Fairchild, and Stephen R. Daley
- Subjects
Drug ,medicine.medical_specialty ,Regulatory T cell ,business.industry ,Mechanism (biology) ,media_common.quotation_subject ,T cell ,Immunology ,T-Lymphocytes, Regulatory ,Organ transplantation ,Transplantation ,Vaccination ,medicine.anatomical_structure ,surgical procedures, operative ,Antigen ,medicine ,Immunology and Allergy ,Animals ,Humans ,Transplantation Tolerance ,business ,media_common - Abstract
Our ability to harness tolerance mechanisms will have a major impact in organ transplantation. It should enable drug minimization, and eventually, the elimination of all immunosuppressive drugs. An improved understanding of the biology of regulatory T cells will make it possible to replace current induction regimens with those favouring the selective vaccination of T cells that prevent graft rejection. Once regulation is established, the continued supply of graft antigens should empower T cell regulation to become the dominant natural mechanism to prevent graft rejection.
- Published
- 2006
37. New tools to identify regulatory T cells
- Author
-
Luis Graca and Repositório da Universidade de Lisboa
- Subjects
Genetically modified mouse ,medicine.drug_class ,Immunology ,chemical and pharmacologic phenomena ,Biology ,Monoclonal antibody ,T-Lymphocytes, Regulatory ,Flow cytometry ,Human disease ,Foxp3 expression ,medicine ,Immunology and Allergy ,Animals ,Humans ,Transcription factor ,medicine.diagnostic_test ,FOXP3 ,hemic and immune systems ,Forkhead Transcription Factors ,Receptors, Interleukin-2 ,Regulatory T cells ,Cell biology ,DNA-Binding Proteins ,Foxp3 ,Monoclonal antibodies ,Tolerance ,Function (biology) - Abstract
© 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim, The lack of tools for direct identification of regulatory T cells (T(reg) cells) at the single-cell level has been one of the major hurdles for the study of T(reg) cells and their involvement in human disease. The identification of the transcription factor Foxp3 as a molecular correlate for T(reg) function offered the opportunity to directly identify T(reg) cells, but until recently adequate reagents were not available. The tools promising the solution for this problem have emerged through the development of transgenic mice in which Foxp3 expression drives the production of fluorescent proteins, as well as the development of mAb that are able to identify Foxp3(+) cells by histology or flow cytometry. With these new tools, the mAb in particular, it will become possible for the first time to directly probe the participation of Foxp3(+) T(reg) cells in human pathology in a quantitative fashion.
- Published
- 2005
38. Regulatory T cells and organ transplantation
- Author
-
Masahide Tone, Yuki Tone, Herman Waldmann, Stephen P. Cobbold, Luis Graca, and Elizabeth Adams
- Subjects
CD4-Positive T-Lymphocytes ,medicine.medical_specialty ,T-Lymphocytes ,Immunology ,Regulator ,T-Cell Antigen Receptor Specificity ,Inflammation ,chemical and pharmacologic phenomena ,Thymus Gland ,Biology ,Organ transplantation ,Immune system ,Antigen ,Antigens, CD ,T-Lymphocyte Subsets ,Transplantation Immunology ,Immune Tolerance ,medicine ,Animals ,Humans ,Immunology and Allergy ,IL-2 receptor ,Models, Immunological ,FOXP3 ,Forkhead Transcription Factors ,Receptors, Interleukin-2 ,Organ Transplantation ,Cell biology ,DNA-Binding Proteins ,Transplantation ,Self Tolerance ,medicine.symptom - Abstract
Empirical studies attempting to explain tolerance to transplanted tissues have demonstrated a regulatory role for CD4+ T-cells. We here propose that regulatory T-cells mediating transplantion tolerance comprise two sets which can functionally complement each other. The CD4+CD25+ “natural regulator” arises in the thymus, and is preoccupied with self-antigens expressed at sites of inflammation. The second, comprising both CD4+CD25+ (FoxP3+) and CD4+CD25− Tr1-like cells are induced by persistent danger-free antigen in the periphery. The role of these cells is to moderate immune responses to prevent tissue destruction while allowing microbial elimination.
- Published
- 2004
39. Regulatory T cells and dendritic cells in transplantation tolerance: molecular markers and mechanisms
- Author
-
Stephen F. Yates, Mark Frewin, Raquel Castejon, Kathleen F. Nolan, Paul J. Fairchild, Herman Waldmann, Stephen P. Cobbold, Elizabeth Adams, Luis Graca, Susan Humm, Diana Zelenika, Alison M. Paterson, Sara A. J. Thompson, and Alain Le Moine
- Subjects
ZAP70 ,Gene Expression Profiling ,T-Lymphocytes ,Immunology ,Dendritic Cells ,Biology ,Natural killer T cell ,Cell biology ,Interleukin 21 ,Antigens, CD ,Interleukin 12 ,Immunology and Allergy ,Cytotoxic T cell ,Animals ,Humans ,Transplantation Tolerance ,IL-2 receptor ,Antigen-presenting cell ,Interleukin 3 - Abstract
Transplantation tolerance can be induced in adult rodents using monoclonal antibodies against coreceptor or costimulation molecules on the surface of T cells. There are currently two well-characterized populations of T cells, demonstrating regulatory capacity: the "natural" CD4+CD25+ T cells and the interleukin (IL)-10-producing Tr1 cells. Although both types of regulatory T cells can induce transplantation tolerance under appropriate conditions, it is not clear whether either one plays any role in drug-induced dominant tolerance, primarily due to a lack of clear-cut molecular or functional markers. Similarly, although dendritic cells (DCs) can be pharmacologically manipulated to promote tolerance, the phenotype of such populations remains poorly defined. We have used serial analysis of gene expression (SAGE) with 29 different T-cell and antigen-presenting cell libraries to identify gene-expression signatures associated with immune regulation. We found that independently derived, regulatory Tr1-like clones were highly concordant in their patterns of gene expression but were quite distinct from CD4+CD25+ regulatory T cells from the spleen. DCs that were treated with the tolerance-enhancing agents IL-10 or vitamin D3 expressed a gene signature reflecting a functional specification in common with the most immature DCs derived from embryonic stem cells.
- Published
- 2003
40. Regulatory T cells in the induction and maintenance of peripheral transplantation tolerance
- Author
-
Stephen P. Cobbold, Luis Graca, Chun-Yen Lin, Elizabeth Adams, and Herman Waldmann
- Subjects
Transplantation ,Transplantation Immunology ,T-Lymphocytes ,Immune Tolerance ,Animals ,Humans - Abstract
It is now possible to induce donor-specific transplantation tolerance in adult rodents using non-depleting monoclonal antibodies against T cell co-receptor and co-stimulation molecules or by immunisation with tolerogenic antigen-presenting cells. It is a common finding of all these models of peripheral tolerance, as well as of various mouse models of autoimmune disease, that regulatory CD4(+) T cells are the principal mediators. There are currently no specific markers for regulatory T cells, but in some autoimmune models their activity has been associated with the expression of activation markers such as CD25 and CTLA4, or anti-inflammatory cytokines such as IL-10 and TGF-beta. CD4(+)CD25(+) T cells from both naïve and tolerised donors are able to transfer tolerance to grafts in lymphopenic recipients, and this may be directly applicable to bone-marrow transplantation. The challenge is now to understand the biological principles that allow such immune re-programming so that they can be safely applied to clinical organ grafting.
- Published
- 2003
41. Both CD4(+)CD25(+) and CD4(+)CD25(-) regulatory cells mediate dominant transplantation tolerance
- Author
-
Elizabeth Adams, Herman Waldmann, Sara K. Thompson, Luis Graca, Stephen P. Cobbold, and Chun-Yen Lin
- Subjects
Graft Rejection ,Adoptive cell transfer ,Immunoconjugates ,Immunology ,Gene Expression ,chemical and pharmacologic phenomena ,Biology ,Immune tolerance ,Abatacept ,Interleukin 21 ,Mice ,Antigen ,Antigens, CD ,T-Lymphocyte Subsets ,Transplantation Immunology ,medicine ,Immune Tolerance ,Immunology and Allergy ,Animals ,Humans ,CTLA-4 Antigen ,IL-2 receptor ,T-cell receptor ,Receptors, Interleukin-2 ,hemic and immune systems ,Skin Transplantation ,medicine.disease ,Adoptive Transfer ,Antigens, Differentiation ,Transplant rejection ,Interleukin-10 ,Transplantation ,CD4 Antigens ,Mice, Inbred CBA ,Interleukin-4 ,Spleen - Abstract
CD4+CD25+ T cells have been proposed as the principal regulators of both self-tolerance and transplantation tolerance. Although CD4+CD25+ T cells do have a suppressive role in transplantation tolerance, so do CD4+CD25− T cells, although 10-fold less potent. Abs to CTLA-4, CD25, IL-10, and IL-4 were unable to abrogate suppression mediated by tolerant spleen cells so excluding any of these molecules as critical agents of suppression. CD4+CD25+ T cells from naive mice can also prevent rejection despite the lack of any previous experience of donor alloantigens. However, this requires many more naive than tolerized cells to provide the same degree of suppression. This suggests that a capacity to regulate transplant rejection pre-exists in naive mice, and may be amplified in “tolerized” mice. Serial analysis of gene expression confirmed that cells sorted into CD4+CD25+ and CD4+CD25− populations were distinct in that they responded to TCR ligation with very different programs of gene expression. Further characterization of the differentially expressed genes may lead to the development of diagnostic tests to monitor the tolerant state.
- Published
- 2002
42. Identification of a cytokine network sustaining neutrophil and Th17 activation in untreated early rheumatoid arthritis
- Author
-
M. Margarida Souto-Carneiro, Rita Cascão, Helena Canhão, Joaquim Polido-Pereira, Luis Graca, Rita A Moura, Ana M. Rodrigues, João Eurico Fonseca, I.P. Perpétuo, H S Rosário, M Viana Queiroz, Ana Filipa Mourão, E Vieira de Sousa, and Repositório da Universidade de Lisboa
- Subjects
Male ,Neutrophils ,medicine.medical_treatment ,lcsh:Medicine ,Arthritis ,Disease ,Lymphocyte Activation ,Arthritis, Rheumatoid ,0302 clinical medicine ,Synovial Fluid ,Immunology and Allergy ,0303 health sciences ,Neutrophil ,General Medicine ,Middle Aged ,Flow Cytometry ,3. Good health ,Cytokine ,Cytokine Network ,030220 oncology & carcinogenesis ,Rheumatoid arthritis ,Cytokines ,Female ,Th17 ,medicine.symptom ,Research Article ,medicine.medical_specialty ,Immunology ,Inflammation ,General Biochemistry, Genetics and Molecular Biology ,03 medical and health sciences ,Rheumatology ,Synovitis ,Internal medicine ,medicine ,Synovial fluid ,Humans ,030304 developmental biology ,030203 arthritis & rheumatology ,Autoimmune disease ,business.industry ,lcsh:R ,Early rheumatoid arthritis ,medicine.disease ,Poster Presentation ,Th17 Cells ,business - Abstract
© 2010 Cascão et al.; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Introduction: Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease characterized by sustained synovitis. Recently, several studies have proposed neutrophils and Th17 cells as key players in the onset and perpetuation of this disease. The main goal of this work was to determine whether cytokines driving neutrophil and Th17 activation are dysregulated in very early rheumatoid arthritis patients with less than 6 weeks of disease duration and before treatment (VERA). Methods: Cytokines related to neutrophil and Th17 activation were quantified in the serum of VERA and established RA patients and compared with other very early arthritis (VEA) and healthy controls. Synovial fluid (SF) from RA and osteoarthritis (OA) patients was also analyzed. Results: VERA patients had increased serum levels of cytokines promoting Th17 polarization (IL-1b and IL-6), as well as IL-8 and Th17-derived cytokines (IL-17A and IL-22) known to induce neutrophil-mediated inflammation. In established RA this pattern is more evident within the SF. Early treatment with methotrexate or corticosteroids led to clinical improvement but without an impact on the cytokine pattern. Conclusions: VERA patients already display increased levels of cytokines related with Th17 polarization and neutrophil recruitment and activation, a dysregulation also found in SF of established RA. 0 Thus, our data suggest that a cytokine-milieu favoring Th17 and neutrophil activity is an early event in RA pathogenesis., This work was supported by a grant from Sociedade Portuguesa de Reumatologia/Schering-Plough 2005. RAM and RC were funded by Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/30247/2006 and SFRH/BD/40513/2007, respectively. MMS-C was funded by Marie Curie Intra-European Fellowship PERG-2008-239422 and a EULAR Young Investigator Award.
- Published
- 2010
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