40 results on '"Soldaini E"'
Search Results
2. Bacterial Endotoxin as a Probe to Investigate Viral Induced Immune Deficiencies
- Author
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Bendinelli, M., primary, Matteucci, D., additional, Conaldi, P. G., additional, and Soldaini, E., additional
- Published
- 1990
- Full Text
- View/download PDF
3. Interactions of Group B Coxsackieviruses with Immunocytes
- Author
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Conaldi, P. G., Matteucci, D., Soldaini, E., Guidi, M., Bendinelli, M., and Schultheiß, Heinz-Peter, editor
- Published
- 1988
- Full Text
- View/download PDF
4. DNA binding specificity of dimeric and tetrameric Stat5 proteins
- Author
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Soldaini, E, Moro, Stefano, Bollenbache, Jr, Schindler, U, and Leonard, Wj
- Published
- 2000
5. Endotoxin suppresses indirect activation of HIV-1 by human herpesvirus 6
- Author
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Ongradi, J., CECCHERINI-NELLI, Luca, Soldaini, E., Bendinelli, M., Conaldi, G., Specter, S., and Friedman, H.
- Subjects
HHV-6 ,Endotoxin ,HIV-1 - Published
- 1990
6. Signaling via the IL-2 and IL-7 Receptors from the Membrane to the Nucleus
- Author
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LEONARD, W.J., primary, IMADA, K., additional, NAKAJIMA, H., additional, PUEL, A., additional, SOLDAINI, E., additional, and JOHN, S., additional
- Published
- 1999
- Full Text
- View/download PDF
7. CIS associates with the interleukin-2 receptor beta chain and inhibits interleukin-2-dependent signaling.
- Author
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Aman, M J, Migone, T S, Sasaki, A, Ascherman, D P, Zhu, M h, Soldaini, E, Imada, K, Miyajima, A, Yoshimura, A, and Leonard, W J
- Abstract
CIS is a cytokine-induced SH2-containing protein that was originally cloned as an interleukin (IL)-3-inducible gene. CIS is known to associate with the IL-3 receptor beta chain and erythropoietin receptor and to inhibit signaling mediated by IL-3 and erythropoietin. We now demonstrate that CIS also interacts with the IL-2 receptor beta chain (IL-2Rbeta). This interaction requires the A region of IL-2Rbeta (residues 313-382), which also mediates the association of IL-2Rbeta with Lck and Jak3. Correspondingly, CIS inhibits functions associated with both of these kinases: Lck-mediated phosphorylation of IL-2Rbeta and IL-2-mediated activation of Stat5. Thus, we demonstrate that CIS can negatively control at least two independent IL-2 signaling pathways. Although a functional SH2 binding domain of CIS was not required for its interaction with IL-2Rbeta in vitro, its phosphotyrosine binding capability was essential for the inhibitory action of CIS. On this basis, we have generated a mutant form of CIS protein with an altered SH2 domain that acts as a dominant negative and should prove useful in further understanding CIS action.
- Published
- 1999
8. Interaction of STAT5 dimers on two low affinity binding sites mediates interleukin 2 (IL-2) stimulation of IL-2 receptor alpha gene transcription.
- Author
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Meyer, W K, Reichenbach, P, Schindler, U, Soldaini, E, and Nabholz, M
- Abstract
Stimulation of the interleukin 2 receptor alpha (IL-2Ralpha) gene by IL-2 is important for the proliferation of antigen-activated T lymphocytes. IL-2 regulates IL-2Ralpha transcription via a conserved 51-nucleotide IL-2 responsive enhancer. Mouse enhancer function depends on cooperative activity of three distinct sites. Two of these are weak binding sites for IL-2-activated STAT5 (signal transducer and activator of transcription) proteins, and mutational analysis indicates that binding of STAT5 to both sites is required for IL-2 responsiveness of the enhancer. The STAT5 dimers interact to form a STAT5 tetramer. The efficiency of tetramerization depends on the relative rotational orientation of the two STAT motifs on the DNA helix. STAT5 tetramerization on enhancer mutants correlates well with the IL-2 responsiveness of these mutants. This provides strong evidence that interactions between STAT dimers binding to a pair of weak binding sites play a biological role by controlling the activity of a well characterized, complex cytokine-responsive enhancer.
- Published
- 1997
9. Mouse interleukin-2 receptor alpha gene expression. Interleukin-1 and interleukin-2 control transcription via distinct cis-acting elements.
- Author
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Sperisen, P, Wang, S M, Soldaini, E, Pla, M, Rusterholz, C, Bucher, P, Corthésy, P, Reichenbach, P, and Nabholz, M
- Abstract
We have shown that interleukin-1 (IL-1) and IL-2 control IL-2 receptor alpha (IL-2R alpha) gene transcription in CD4-CD8- murine T lymphocyte precursors. Here we map the cis-acting elements that mediate interleukin responsiveness of the mouse IL-2R alpha gene using a thymic lymphoma-derived hybridoma (PC60). The transcriptional response of the IL-2R alpha gene to stimulation by IL-1 + IL-2 is biphasic. IL-1 induces a rapid, protein synthesis-independent appearance of IL-2R alpha mRNA that is blocked by inhibitors of NF-kappa B activation. It also primes cells to become IL-2 responsive and thereby prepares the second phase, in which IL-2 induces a 100-fold further increase in IL-2R alpha transcripts. Transient transfection experiments show that several elements in the promoter-proximal region of the IL-2R alpha gene contribute to IL-1 responsiveness, most importantly an NF-kappa B site conserved in the human and mouse gene. IL-2 responsiveness, on the other hand, depends on a 78-nucleotide segment 1.3 kilobases upstream of the major transcription start site. This segment functions as an IL-2-inducible enhancer and lies within a region that becomes DNase I hypersensitive in normal T cells in which IL-2R alpha expression has been induced. IL-2 responsiveness requires three distinct elements within the enhancer. Two of these are potential binding sites for STAT proteins.
- Published
- 1995
10. Mouse interleukin-2 receptor alpha gene expression. Delimitation of cis-acting regulatory elements in transgenic mice and by mapping of DNase-I hypersensitive sites.
- Author
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Soldaini, E, Pla, M, Beermann, F, Espel, E, Corthésy, P, Barangé, S, Waanders, G A, MacDonald, H R, and Nabholz, M
- Abstract
The alpha chain of the interleukin-2 receptor (IL-2R alpha) is a key regulator of lymphocyte proliferation. To analyze the mechanisms controlling its expression in normal cells, we used the 5'-flanking region (base pairs -2539/+93) of the mouse gene to drive chloramphenicol acetyltransferase expression in four transgenic mouse lines. Constitutive transgene activity was restricted to lymphoid organs. In mature T lymphocytes, transgene and endogenous IL-2R alpha gene expression was stimulated by concanavalin A and up-regulated by IL-2 with very similar kinetics. In thymic T cell precursors, IL-1 and IL-2 cooperatively induced transgene and IL-2R alpha gene expression. These results show that regulation of the endogenous IL-2R alpha gene occurs mainly at the transcriptional level. They demonstrate that cis-acting elements in the 5'-flanking region present in the transgene confer correct tissue specificity and inducible expression in mature T cells and their precursors in response to antigen, IL-1, and IL-2. In a complementary approach, we screened the 5' end of the endogenous IL-2R alpha gene for DNase-I hypersensitive sites. We found three lymphocyte specific DNase-I hypersensitive sites. Two, at -0.05 and -5.3 kilobase pairs, are present in resting T cells. A third site appears at -1.35 kilobase pairs in activated T cells. It co-localizes with IL-2-responsive elements identified by transient transfection experiments.
- Published
- 1995
11. Mouse interleukin-2 receptor alpha gene expression. Delimitation of cis-acting regulatory elements in transgenic mice and by mapping of DNase-I hypersensitive sites
- Author
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Soldaini, E., Pla, M., Beermann, F., Espel, E., Corthesy, P., Barange, S., Waanders, G. A., MacDonald, H. R., and Nabholz, M.
- Abstract
The alpha chain of the interleukin-2 receptor (IL-2R alpha) is a key regulator of lymphocyte proliferation. To analyze the mechanisms controlling its expression in normal cells, we used the 5'-flanking region (base pairs -2539/+93) of the mouse gene to drive chloramphenicol acetyltransferase expression in four transgenic mouse lines. Constitutive transgene activity was restricted to lymphoid organs. In mature T lymphocytes, transgene and endogenous IL-2R alpha gene expression was stimulated by concanavalin A and up-regulated by IL-2 with very similar kinetics. In thymic T cell precursors, IL-1 and IL-2 cooperatively induced transgene and IL-2R alpha gene expression. These results show that regulation of the endogenous IL-2R alpha gene occurs mainly at the transcriptional level. They demonstrate that cis-acting elements in the 5'-flanking region present in the transgene confer correct tissue specificity and inducible expression in mature T cells and their precursors in response to antigen, IL-1, and IL-2. In a complementary approach, we screened the 5' end of the endogenous IL-2R alpha gene for DNase-I hypersensitive sites. We found three lymphocyte specific DNase-I hypersensitive sites. Two, at -0.05 and -5.3 kilobase pairs, are present in resting T cells. A third site appears at -1.35 kilobase pairs in activated T cells. It co-localizes with IL-2-responsive elements identified by transient transfection experiments.
12. Mouse interleukin-2 receptor alpha gene expression. Interleukin-1 and interleukin-2 control transcription via distinct cis-acting elements
- Author
-
Sperisen, P., Wang, S. M., Soldaini, E., Pla, M., Rusterholz, C., Bucher, P., Corthesy, P., Reichenbach, P., and Nabholz, M.
- Abstract
We have shown that interleukin-1 (IL-1) and IL-2 control IL-2 receptor alpha (IL-2R alpha) gene transcription in CD4-CD8- murine T lymphocyte precursors. Here we map the cis-acting elements that mediate interleukin responsiveness of the mouse IL-2R alpha gene using a thymic lymphoma-derived hybridoma (PC60). The transcriptional response of the IL-2R alpha gene to stimulation by IL-1 + IL-2 is biphasic. IL-1 induces a rapid, protein synthesis-independent appearance of IL-2R alpha mRNA that is blocked by inhibitors of NF-kappa B activation. It also primes cells to become IL-2 responsive and thereby prepares the second phase, in which IL-2 induces a 100-fold further increase in IL-2R alpha transcripts. Transient transfection experiments show that several elements in the promoter-proximal region of the IL-2R alpha gene contribute to IL-1 responsiveness, most importantly an NF-kappa B site conserved in the human and mouse gene. IL-2 responsiveness, on the other hand, depends on a 78-nucleotide segment 1.3 kilobases upstream of the major transcription start site. This segment functions as an IL-2-inducible enhancer and lies within a region that becomes DNase I hypersensitive in normal T cells in which IL-2R alpha expression has been induced. IL-2 responsiveness requires three distinct elements within the enhancer. Two of these are potential binding sites for STAT proteins.
13. Mouse IL-2Rα gene regulation by IL-1 and IL-2
- Author
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Soldaini, E., Sperisen, P., Pla, M., Wang, S.-M., Rusterholz, C., Reichenbach, P., Corthesy, P., Wilson, A., Beermann, F., and Nabholz, M.
- Published
- 1994
- Full Text
- View/download PDF
14. Dissecting the Human Response to Staphylococcus aureus Systemic Infections.
- Author
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Leuzzi R, Bodini M, Thomsen IP, Soldaini E, Bartolini E, Muzzi A, Clemente B, Galletti B, Manetti AGO, Giovani C, Censini S, Budroni S, Spensieri F, Borgogni E, Rossi Paccani S, Margarit I, Bagnoli F, Giudice GD, and Creech CB
- Subjects
- Adult, Antibodies, Bacterial blood, Antigens, Bacterial immunology, Child, Cytokines blood, Humans, Immunoglobulin G blood, Protein Array Analysis, Staphylococcal Infections blood, Staphylococcal Infections genetics, Staphylococcus aureus immunology, Virulence Factors immunology, Staphylococcal Infections immunology
- Abstract
Staphylococcus aureus is a common human commensal and the leading cause of diverse infections. To identify distinctive parameters associated with infection and colonization, we compared the immune and inflammatory responses of patients with a diagnosis of invasive S. aureus disease to healthy donors. We analyzed the inflammatory responses founding a pattern of distinctive cytokines significantly higher in the patients with invasive disease. The measure of antibody levels revealed a wide antibody responsiveness from all subjects to most of the antigens, with significantly higher response for some antigens in the invasive patients compared to control. Moreover, functional antibodies against toxins distinctively associated with the invasive disease. Finally, we examined the genomic variability of isolates, showing no major differences in genetic distribution compared to a panel of representative strains. Overall, our study shows specific signatures of cytokines and functional antibodies in patients with different primary invasive diseases caused by S. aureus . These data provide insight into human responses towards invasive staphylococcal infections and are important for guiding the identification of novel preventive and therapeutic interventions against S. aureus ., Competing Interests: All authors except GG, SC, IT, and CC are employees of the GSK group of companies. FB and IM hold shares and/or restricted shares in the GSK group of companies. GG was employed by the GSK group of companies during the conduct of this study and held stock options and stocks in the GSK group of companies as part of his employee remuneration. SC was employed by the GSK group of companies during the conduct of this study. FB holds pending and issued patents on S. aureus vaccine formulations. IM and RL are listed as inventor on patents owned by the GSK group of companies. BC has non-financial support from the University of Siena outside the submitted work. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The authors declare that this study received funding from Novartis Vaccines and Diagnostics Srl. The funders had the following involvement with the study: study design, conduct, analysis and data interpretation., (Copyright © 2021 Leuzzi, Bodini, Thomsen, Soldaini, Bartolini, Muzzi, Clemente, Galletti, Manetti, Giovani, Censini, Budroni, Spensieri, Borgogni, Rossi Paccani, Margarit, Bagnoli, Giudice and Creech.)
- Published
- 2021
- Full Text
- View/download PDF
15. Staphylococcus aureus Vaccine Research and Development: The Past, Present and Future, Including Novel Therapeutic Strategies.
- Author
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Clegg J, Soldaini E, McLoughlin RM, Rittenhouse S, Bagnoli F, and Phogat S
- Subjects
- Adjuvants, Immunologic, Animals, Antigens, Bacterial immunology, Clinical Trials as Topic, Extracellular Vesicles immunology, Glycoconjugates immunology, Gram-Negative Bacteria immunology, Host-Pathogen Interactions, Humans, Immunity, Cellular, Immunity, Humoral, Immunogenicity, Vaccine, In Vitro Techniques, Mice, Models, Animal, Nucleic Acid-Based Vaccines immunology, Periplasm immunology, Recombinant Proteins immunology, Translational Science, Biomedical, Vaccines, Attenuated immunology, Vaccines, Synthetic immunology, Staphylococcal Infections prevention & control, Staphylococcal Vaccines immunology, Staphylococcal Vaccines therapeutic use, Staphylococcus aureus immunology, Vaccine Development
- Abstract
Staphylococcus aureus is one of the most important human pathogens worldwide. Its high antibiotic resistance profile reinforces the need for new interventions like vaccines in addition to new antibiotics. Vaccine development efforts against S. aureus have failed so far however, the findings from these human clinical and non-clinical studies provide potential insight for such failures. Currently, research is focusing on identifying novel vaccine formulations able to elicit potent humoral and cellular immune responses. Translational science studies are attempting to discover correlates of protection using animal models as well as in vitro and ex vivo models assessing efficacy of vaccine candidates. Several new vaccine candidates are being tested in human clinical trials in a variety of target populations. In addition to vaccines, bacteriophages, monoclonal antibodies, centyrins and new classes of antibiotics are being developed. Some of these have been tested in humans with encouraging results. The complexity of the diseases and the range of the target populations affected by this pathogen will require a multipronged approach using different interventions, which will be discussed in this review., Competing Interests: JC is a PhD fellow who is enrolled in the School of Biochemistry and Immunology at Trinity College Dublin and participates in a postgraduate studentship program at GSK. ES, SR, FB, and SP are employees of the GSK group of companies. The remaining author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Clegg, Soldaini, McLoughlin, Rittenhouse, Bagnoli and Phogat.)
- Published
- 2021
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16. Staphylococcus aureus -Specific Tissue-Resident Memory CD4 + T Cells Are Abundant in Healthy Human Skin.
- Author
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Hendriks A, Mnich ME, Clemente B, Cruz AR, Tavarini S, Bagnoli F, and Soldaini E
- Subjects
- Adult, Cytokines biosynthesis, Female, Humans, Interleukin-17 biosynthesis, Middle Aged, Skin microbiology, CD4-Positive T-Lymphocytes immunology, Immunologic Memory immunology, Skin immunology, Staphylococcus aureus immunology
- Abstract
The skin is an immunocompetent tissue that harbors several kinds of immune cells and a plethora of commensal microbes constituting the skin microbiome. Staphylococcus aureus is a prominent skin pathogen that colonizes a large proportion of the human population. We currently have an incomplete understanding of the correlates of protection against S. aureus infection, however genetic and experimental evidence has shown that CD4
+ T cells play a key role in orchestrating a protective anti- S. aureus immune response. A high S. aureus -specific memory CD4+ T cell response has been reported in the blood of healthy subjects. Since T cells are more abundant in the skin than in blood, we hypothesized that S. aureus -specific CD4+ T cells could be present in the skin of healthy individuals. Indeed, we observed proliferation of tissue-resident memory CD4+ T cells and production of IL-17A, IL-22, IFN-γ and TNF-β by cells isolated from abdominal skin explants in response to heat-killed S. aureus . Remarkably, these cytokines were produced also during an ex vivo epicutaneous S. aureus infection of human skin explants. These findings highlight the importance of tissue-resident memory CD4+ T cells present at barrier sites such as the skin, a primary entry site for S. aureus . Further phenotypical and functional characterization of these cells will ultimately aid in the development of novel vaccine strategies against this elusive pathogen., Competing Interests: AH, MEM, and ARC are Ph.D. fellows and are enrolled in the Infection and Immunity Ph.D. program, part of the graduate school of Life Sciences at Utrecht University and participated in a post graduate studentship program at GSK. BC was a PhD student from the University of Siena funded by GSK. ST, FB, and ES are employees of the GSK group of companies. FB hold shares in the GSK group of companies and holds pending and issued patents (WO/2019/158537, WO/2015/144691, WO/2015/144653, WO/2015/144655, WO/2014/033190, WO/2014/033191, WO/2014/033192, WO/2014/033193, WO/2013/030378, and WO/2010/119343) on S. aureus vaccine formulations., (Copyright © 2021 Hendriks, Mnich, Clemente, Cruz, Tavarini, Bagnoli and Soldaini.)- Published
- 2021
- Full Text
- View/download PDF
17. Correction to: Human Organotypic Models for Anti-infective Research.
- Author
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Hendriks A, Cruz AR, Soldaini E, Manetti AGO, and Bagnoli F
- Published
- 2021
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18. Targeting Skin-Resident Memory T Cells via Vaccination to Combat Staphylococcus aureus Infections.
- Author
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Clegg J, Soldaini E, Bagnoli F, and McLoughlin RM
- Subjects
- Animals, Humans, Mice, Staphylococcal Vaccines, Vaccination, CD4-Positive T-Lymphocytes immunology, Immunologic Memory, Skin cytology, Skin immunology, Staphylococcal Infections therapy, Staphylococcus aureus
- Abstract
Tissue-resident memory T cells are important in adaptive immunity against many infections, rendering these cells attractive potential targets in vaccine development. Genetic and experimental evidence highlights the importance of cellular immunity in protection from Staphylococcus aureus skin infections, yet skin-resident memory T cells are, thus far, an untested component of immunity during such infections. Novel methods of generating and sampling vaccine-induced skin memory T cells are paralleled by discoveries of global, skin-wide immunosurveillance. We propose skin-resident memory CD4
+ T cells as a potential missing link in the search for correlates of protection during S. aureus infections. A better appreciation of their phenotypes and functions could accelerate the development of preventive vaccines against this highly virulent and antibiotic-resistant pathogen., (Copyright © 2020 The Author(s). Published by Elsevier Ltd.. All rights reserved.)- Published
- 2021
- Full Text
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19. Human Three-Dimensional Models for Studying Skin Pathogens.
- Author
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Boero E, Mnich ME, Manetti AGO, Soldaini E, Grimaldi L, and Bagnoli F
- Subjects
- Animals, Humans, Symbiosis, Bacteria, Fungi
- Abstract
Skin is the most exposed surface of the human body, separating the microbe-rich external environment, from the sterile inner part. When skin is breached or its homeostasis is perturbed, bacterial, fungal and viral pathogens can cause local infections or use the skin as an entry site to spread to other organs. In the last decades, it has become clear that skin provides niches for permanent microbial colonization, and it actively interacts with microorganisms. This crosstalk promotes skin homeostasis and immune maturation, preventing expansion of harmful organisms. Skin commensals, however, are often found to be skin most prevalent and dangerous pathogens. Despite the medical interest, mechanisms of colonization and invasion for most skin pathogens are poorly understood. This limitation is due to the lack of reliable skin models. Indeed, animal models do not adequately mimic neither the anatomy nor the immune response of human skin. Human 3D skin models overcome these limitations and can provide new insights into the molecular mechanisms of microbial pathogenesis. Herein, we address the strengths and weaknesses of different types of human skin models and we review the main findings obtained using these models to study skin pathogens.
- Published
- 2021
- Full Text
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20. Human Organotypic Models for Anti-infective Research.
- Author
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Hendriks A, Cruz AR, Soldaini E, Manetti AGO, and Bagnoli F
- Subjects
- Animals, Humans, Models, Animal, Models, Biological, Skin
- Abstract
The use of human organotypic models for biomedical research is experiencing a significant increase due to their biological relevance, the possibility to perform high-throughput analyses, and their cost efficiency. In the field of anti-infective research, comprising the search for novel antipathogenic treatments including vaccines, efforts have been made to reduce the use of animal models. That is due to two main reasons: unreliability of data obtained with animal models and the increasing willingness to reduce the use of animals in research for ethical reasons. Human three-dimensional (3-D) models may substitute and/or complement in vivo studies, to increase the translational value of preclinical data. Here, we provide an overview of recent studies utilizing human organotypic models, resembling features of the cervix, intestine, lungs, brain, and skin in the context of anti-infective research. Furthermore, we focus on the future applications of human skin models and present methodological protocols to culture human skin equivalents and human skin explants.
- Published
- 2021
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21. One Dose of Staphylococcus aureus 4C-Staph Vaccine Formulated with a Novel TLR7-Dependent Adjuvant Rapidly Protects Mice through Antibodies, Effector CD4+ T Cells, and IL-17A.
- Author
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Mancini F, Monaci E, Lofano G, Torre A, Bacconi M, Tavarini S, Sammicheli C, Arcidiacono L, Galletti B, Laera D, Pallaoro M, Tuscano G, Fontana MR, Bensi G, Grandi G, Rossi-Paccani S, Nuti S, Rappuoli R, De Gregorio E, Bagnoli F, Soldaini E, and Bertholet S
- Subjects
- Adjuvants, Immunologic, Animals, Antibodies, Neutralizing immunology, CD4-Positive T-Lymphocytes cytology, Cytokines metabolism, Female, Mice, Mice, Inbred C57BL, Spleen metabolism, Spleen pathology, Staphylococcal Infections immunology, Staphylococcal Infections mortality, Staphylococcus aureus genetics, Survival Rate, Th1 Cells immunology, Th17 Cells immunology, Toll-Like Receptor 7 immunology, Antibodies, Bacterial immunology, CD4-Positive T-Lymphocytes immunology, Interleukin-17 metabolism, Staphylococcal Infections prevention & control, Staphylococcal Vaccines immunology, Staphylococcus aureus immunology, Toll-Like Receptor 7 metabolism
- Abstract
A rapidly acting, single dose vaccine against Staphylococcus aureus would be highly beneficial for patients scheduled for major surgeries or in intensive care units. Here we show that one immunization with a multicomponent S. aureus candidate vaccine, 4C-Staph, formulated with a novel TLR7-dependent adjuvant, T7-alum, readily protected mice from death and from bacterial dissemination, both in kidney abscess and peritonitis models, outperforming alum-formulated vaccine. This increased efficacy was paralleled by higher vaccine-specific and α-hemolysin-neutralizing antibody titers and Th1/Th17 cell responses. Antibodies played a crucial protective role, as shown by the lack of protection of 4C-Staph/T7-alum vaccine in B-cell-deficient mice and by serum transfer experiments. Depletion of effector CD4+ T cells not only reduced survival but also increased S. aureus load in kidneys of mice immunized with 4C-Staph/T7-alum. The role of IL-17A in the control of bacterial dissemination in 4C-Staph/T7-alum vaccinated mice was indicated by in vivo neutralization experiments. We conclude that single dose 4C-Staph/T7-alum vaccine promptly and efficiently protected mice against S. aureus through the combined actions of antibodies, CD4+ effector T cells, and IL-17A. These data suggest that inclusion of an adjuvant that induces not only fast antibody responses but also IL-17-producing cell-mediated effector responses could efficaciously protect patients scheduled for major surgeries or in intensive care units.
- Published
- 2016
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22. MF59- and Al(OH)3-Adjuvanted Staphylococcus aureus (4C-Staph) Vaccines Induce Sustained Protective Humoral and Cellular Immune Responses, with a Critical Role for Effector CD4 T Cells at Low Antibody Titers.
- Author
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Monaci E, Mancini F, Lofano G, Bacconi M, Tavarini S, Sammicheli C, Arcidiacono L, Giraldi M, Galletti B, Rossi Paccani S, Torre A, Fontana MR, Grandi G, de Gregorio E, Bensi G, Chiarot E, Nuti S, Bagnoli F, Soldaini E, and Bertholet S
- Abstract
Staphylococcus aureus (S. aureus) is an important opportunistic pathogen that may cause invasive life-threatening infections, like sepsis and pneumonia. Due to the increasing antibiotic resistance, the development of an effective vaccine against S. aureus is needed. Although a correlate of protection against staphylococcal diseases is not yet established, several findings suggest that both antibodies and CD4 T cells might contribute to optimal immunity. In this study, we show that adjuvanting a multivalent vaccine (4C-Staph) with MF59, an oil-in-water emulsion licensed in human vaccines, further potentiated antigen-specific IgG titers and CD4 T-cell responses compared to alum and conferred protection in the peritonitis model of S. aureus infection. Moreover, we showed that MF59- and alum-adjuvanted 4C-Staph vaccines induced persistent antigen-specific humoral and T-cell responses, and protected mice from infection up to 4 months after immunization. Furthermore, 4C-Staph formulated with MF59 was used to investigate which immune compartment is involved in vaccine-induced protection. Using CD4 T cell-depleted mice or B cell-deficient mice, we demonstrated that both T and B-cell responses contributed to 4C-Staph vaccine-mediated protective immunity. However, the role of CD4 T cells seemed more evident in the presence of low-antibody responses. This study provides preclinical data further supporting the use of the adjuvanted 4C-Staph vaccines against S. aureus diseases, and provides critical insights on the correlates of protective immunity necessary to combat this pathogen.
- Published
- 2015
- Full Text
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23. Phagocyte subsets and lymphocyte clonal deletion behind ineffective immune response to Staphylococcus aureus.
- Author
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Pozzi C, Lofano G, Mancini F, Soldaini E, Speziale P, De Gregorio E, Rappuoli R, Bertholet S, Grandi G, and Bagnoli F
- Subjects
- Clonal Deletion, Humans, Immune Evasion, Lymphocytes cytology, Lymphocytes immunology, Phagocytes immunology, Staphylococcal Infections immunology, Staphylococcus aureus immunology
- Abstract
Lack of known mechanisms of protection against Staphylococcus aureus in humans is hindering development of efficacious vaccines. Preclinical as well as clinical data suggest that antibodies play an important role against S. aureus. For instance, certain hypogammaglobulinaemic patients are at increased risk of staphylococcal infections. However, development of effective humoral response may be dampened by converging immune-evasion mechanisms of S. aureus. We hypothesize that B-cell proliferation induced by staphylococcal protein A (SpA) and continuous antigen exposure, without the proper T-cell help and cytokine stimuli, leads to antigen-activated B-cell deletion and anergy. Recent findings suggest an important role of type I neutrophils (PMN-I) and conventionally activated macrophages (M1) against S. aureus, while alternatively activated macrophages (M2) favour biofilm persistence and sepsis. In addition, neutrophil-macrophage cooperation promotes extravasation and activation of neutrophils as well as clearance of bacteria ensnared in neutrophil extracellular traps. Activation of these processes is modulated by cytokines and T cells. Indeed, low CD4(+) T-cell counts represent an important risk factor for skin infections and bacteraemia in patients. Altogether, these observations could lead to the identification of predictive correlates of protection and ways for shifting the balance of the response to the benefit of the host through vaccination., (© FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2015
- Full Text
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24. Oil-in-Water Emulsion MF59 Increases Germinal Center B Cell Differentiation and Persistence in Response to Vaccination.
- Author
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Lofano G, Mancini F, Salvatore G, Cantisani R, Monaci E, Carrisi C, Tavarini S, Sammicheli C, Rossi Paccani S, Soldaini E, Laera D, Finco O, Nuti S, Rappuoli R, De Gregorio E, Bagnoli F, and Bertholet S
- Subjects
- Adjuvants, Immunologic, Animals, Antibodies, Bacterial immunology, Antibody Specificity immunology, Antigens, CD metabolism, B-Lymphocytes metabolism, Bacterial Toxins immunology, Chemotaxis, Leukocyte immunology, Female, Hemolysin Proteins immunology, Immunophenotyping, Lymph Nodes immunology, Lymphocyte Activation immunology, Mice, Phenotype, Staphylococcal Vaccines, B-Lymphocytes cytology, B-Lymphocytes immunology, Cell Differentiation, Germinal Center cytology, Germinal Center immunology, Polysorbates, Squalene immunology, Vaccination
- Abstract
Induction of persistent protective immune responses is a key attribute of a successful vaccine formulation. MF59 adjuvant, an oil-in-water emulsion used in human vaccines, is known to induce persistent high-affinity functional Ab titers and memory B cells, but how it really shapes the Ag-specific B cell compartment is poorly documented. In this study, we characterized the Ab- and Ag-specific B cell compartment in wild-type mice immunized with HlaH35L, a Staphylococcus aureus Ag known to induce measurable functional Ab responses, formulated with MF59 or aluminum salts, focusing on germinal centers (GC) in secondary lymphoid organs. Taking advantage of single-cell flow cytometry analyses, HlaH35L-specific B cells were characterized for the expression of CD38 and GL-7, markers of memory and GC, respectively, and for CD80 and CD73 activation markers. We demonstrated that immunization with MF59-, but not aluminum salt-adjuvanted HlaH35L, induced expanded Ag-specific CD73(+)CD80(-) GC B cells in proximal- and distal-draining lymph nodes, and promoted the persistence of GC B cells, detected up to 4 mo after immunization. In addition to increasing GC B cells, MF59-adjuvanted HlaH35L also increased the frequency of T follicular helper cells. This work extends previous knowledge regarding adaptive immune responses to MF59-adjuvanted vaccines, and, to our knowledge, for the first time an adjuvant used in human licensed products is shown to promote strong and persistent Ag-specific GC responses that might benefit the rational design of new vaccination strategies., (Copyright © 2015 by The American Association of Immunologists, Inc.)
- Published
- 2015
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25. NAD-dependent ADP-ribosylation of the human antimicrobial and immune-modulatory peptide LL-37 by ADP-ribosyltransferase-1.
- Author
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Picchianti M, Russo C, Castagnini M, Biagini M, Soldaini E, and Balducci E
- Subjects
- Adenosine Diphosphate Ribose metabolism, Animals, Arginine metabolism, Cell Line, Cell Membrane metabolism, GPI-Linked Proteins metabolism, Humans, Immunomodulation, Mass Spectrometry, Cathelicidins, ADP Ribose Transferases metabolism, Antimicrobial Cationic Peptides metabolism, NAD metabolism
- Abstract
LL-37 is a cationic peptide belonging to the cathelicidin family that has antimicrobial and immune-modulatory properties. Here we show that the mammalian mono-ADP-ribosyltransferase-1 (ART1), which selectively transfers the ADP-ribose moiety from NAD to arginine residues, ADP-ribosylates LL-37 in vitro. The incorporation of ADP-ribose was first observed by Western blot analysis and then confirmed by MALDI-TOF. Mass-spectrometry showed that up to four of the five arginine residues present in LL-37 could be ADP-ribosylated on the same peptide when incubated at a high NAD concentration in the presence of ART1. The attachment of negatively charged ADP-ribose moieties considerably alters the positive charge of the arginine residues thus reducing the cationicity of LL-37. The cationic nature of LL-37 is key for its ability to interact with cell membranes or negatively charged biomolecules, such as DNA, RNA, F-actin and glycosaminoglycans. Thus, the ADP-ribosylation of LL-37 is expected to have the potential to modulate LL-37 biological activities in several physiological and pathological settings., (© The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.)
- Published
- 2015
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26. Vaccine composition formulated with a novel TLR7-dependent adjuvant induces high and broad protection against Staphylococcus aureus.
- Author
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Bagnoli F, Fontana MR, Soldaini E, Mishra RP, Fiaschi L, Cartocci E, Nardi-Dei V, Ruggiero P, Nosari S, De Falco MG, Lofano G, Marchi S, Galletti B, Mariotti P, Bacconi M, Torre A, Maccari S, Scarselli M, Rinaudo CD, Inoshima N, Savino S, Mori E, Rossi-Paccani S, Baudner B, Pallaoro M, Swennen E, Petracca R, Brettoni C, Liberatori S, Norais N, Monaci E, Bubeck Wardenburg J, Schneewind O, O'Hagan DT, Valiante NM, Bensi G, Bertholet S, De Gregorio E, Rappuoli R, and Grandi G
- Subjects
- Abscess pathology, Adaptive Immunity, Animals, Anti-Bacterial Agents chemistry, Antibodies, Bacterial immunology, Antigens immunology, Humans, Mice, Models, Animal, Staphylococcal Infections immunology, Staphylococcus aureus, Th1 Cells immunology, Adjuvants, Immunologic pharmacology, Staphylococcal Infections prevention & control, Staphylococcal Vaccines chemistry, Toll-Like Receptor 7 chemistry
- Abstract
Both active and passive immunization strategies against Staphylococcus aureus have thus far failed to show efficacy in humans. With the attempt to develop an effective S. aureus vaccine, we selected five conserved antigens known to have different roles in S. aureus pathogenesis. They include the secreted factors α-hemolysin (Hla), ess extracellular A (EsxA), and ess extracellular B (EsxB) and the two surface proteins ferric hydroxamate uptake D2 and conserved staphylococcal antigen 1A. The combined vaccine antigens formulated with aluminum hydroxide induced antibodies with opsonophagocytic and functional activities and provided consistent protection in four mouse models when challenged with a panel of epidemiologically relevant S. aureus strains. The importance of antibodies in protection was demonstrated by passive transfer experiments. Furthermore, when formulated with a toll-like receptor 7-dependent (TLR7) agonist recently designed and developed in our laboratories (SMIP.7-10) adsorbed to alum, the five antigens provided close to 100% protection against four different staphylococcal strains. The new formulation induced not only high antibody titers but also a Th1 skewed immune response as judged by antibody isotype and cytokine profiles. In addition, low frequencies of IL-17-secreting T cells were also observed. Altogether, our data demonstrate that the rational selection of mixtures of conserved antigens combined with Th1/Th17 adjuvants can lead to promising vaccine formulations against S. aureus.
- Published
- 2015
- Full Text
- View/download PDF
27. Small molecule Toll-like receptor 7 agonists localize to the MHC class II loading compartment of human plasmacytoid dendritic cells.
- Author
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Russo C, Cornella-Taracido I, Galli-Stampino L, Jain R, Harrington E, Isome Y, Tavarini S, Sammicheli C, Nuti S, Mbow ML, Valiante NM, Tallarico J, De Gregorio E, and Soldaini E
- Subjects
- Adenine pharmacokinetics, Antineoplastic Agents pharmacokinetics, Cells, Cultured, Enzyme Inhibitors pharmacology, Fluorescent Antibody Technique, Humans, Imiquimod, Macrolides pharmacology, Proton-Translocating ATPases antagonists & inhibitors, Quinolines chemistry, Quinolines pharmacokinetics, Toll-Like Receptor 7 metabolism, Adenine analogs & derivatives, Aminoquinolines pharmacokinetics, Dendritic Cells metabolism, Fluorescent Dyes, Genes, MHC Class II physiology, Imidazoles pharmacokinetics, Toll-Like Receptor 7 agonists
- Abstract
TLR7 and TLR8 are intracellular sensors activated by single-stranded RNA species generated during viral infections. Various synthetic small molecules can also activate TLR7 or TLR8 or both through an unknown mechanism. Notably, direct interaction between small molecules and TLR7 or TLR8 has never been shown. To shed light on how small molecule agonists target TLRs, we labeled 2 imidazoquinolines, resiquimod and imiquimod, and one adenine-based compound, SM360320, with 2 different fluorophores [5(6) carboxytetramethylrhodamine and Alexa Fluor 488] and monitored their intracellular localization in human plasmacytoid dendritic cells (pDCs). All fluorescent compounds induced the production of IFN-α, TNF-α, and IL-6 and the up-regulation of CD80 and CD86 by pDCs showing they retained TLR7-stimulating activity. Confocal imaging of pDCs showed that, similar to CpG-B, all compounds concentrated in the MHC class II loading compartment (MIIC), identified as lysosome-associated membrane protein 1(+), CD63, and HLA-DR(+) endosomes. Treatment of pDCs with bafilomycin A, an antagonist of the vacuolar-type proton ATPase controlling endosomal acidification, prevented the accumulation of small molecule TLR7 agonists, but not of CpG-B, in the MIIC. These results indicate that a pH-driven concentration of small molecule TLR7 agonists in the MIIC is required for pDC activation.
- Published
- 2011
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28. Helicobacter pylori induces activation of human peripheral γδ+ T lymphocytes.
- Author
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Romi B, Soldaini E, Pancotto L, Castellino F, Del Giudice G, and Schiavetti F
- Subjects
- Coculture Techniques, Flow Cytometry, Green Fluorescent Proteins metabolism, Humans, Lymphocyte Activation, Microscopy, Confocal methods, Receptors, Antigen, T-Cell metabolism, Risk Factors, CD3 Complex metabolism, Helicobacter Infections blood, Helicobacter pylori metabolism, Receptors, Antigen, T-Cell, gamma-delta metabolism, T-Lymphocytes metabolism, T-Lymphocytes microbiology
- Abstract
Helicobacter pylori is a gram-negative bacterium that causes gastric and duodenal diseases in humans. Despite a robust antibody and cellular immune response, H. pylori infection persists chronically. To understand if and how H. pylori could modulate T cell activation, in the present study we investigated in vitro the interaction between H. pylori and human T lymphocytes freshly isolated from peripheral blood of H. pylori-negative donors. A direct interaction of live, but not killed bacteria with purified CD3+ T lymphocytes was observed by microscopy and confirmed by flow cytometry. Live H. pylori activated CD3+ T lymphocytes and predominantly γδ+ T cells bearing the TCR chain Vδ2. Upon interaction with H. pylori, these cells up-regulated the activation molecule CD69 and produced cytokines (such as TNFα, IFNγ) and chemokines (such as MIP-1β, RANTES) in a non-antigen-specific manner. This activation required viable H. pylori and was not exhibited by other gram-negative bacteria. The cytotoxin-associated antigen-A (CagA), was at least partially responsible of this activation. Our results suggest that H. pylori can directly interact with T cells and modulate the response of γδ+ T cells, thereby favouring an inflammatory environment which can contribute to the chronic persistence of the bacteria and eventually to the gastric pathology.
- Published
- 2011
- Full Text
- View/download PDF
29. Coligation of the hepatitis C virus receptor CD81 with CD28 primes naive T lymphocytes to acquire type 2 effector function.
- Author
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Serra A, Nuti S, Tavarini S, Sammicheli C, Rosa D, Saletti G, Soldaini E, Abrignani S, and Wack A
- Subjects
- CD4-Positive T-Lymphocytes cytology, CD4-Positive T-Lymphocytes metabolism, CD8-Positive T-Lymphocytes cytology, CD8-Positive T-Lymphocytes metabolism, Cell Differentiation immunology, Cell Membrane immunology, Cell Proliferation, Cells, Cultured, Cytokines immunology, Cytokines metabolism, Humans, Immunologic Memory immunology, Lymphocyte Activation immunology, Protein Binding, Tetraspanin 28, Antigens, CD immunology, CD28 Antigens immunology, CD4-Positive T-Lymphocytes immunology, CD8-Positive T-Lymphocytes immunology, Hepacivirus immunology, Immunity, Innate immunology
- Abstract
Costimuli provide supplementary signals required by naive T cells to become fully activated upon Ag encounter. Tetraspanins are a large family of transmembrane proteins that can costimulate T cells when engaged in vitro. In this study, we describe for the first time that coligation of the tetraspanins CD81, CD82, or CD9 with the costimulatory molecule CD28 in vitro leads to proliferation of naive T cells. When activated through this pathway, both CD4+ and CD8+ naive T cells differentiate into type 2 effector cells, which produce IL-4, IL-5, IL-13, and IL-10, together with IL-2 and TNF-alpha, but little to no IFN-gamma. These effector cells descend from precursors that display early and strong production of IL-4, STAT6 phosphorylation, and up-regulation of the transcription factor GATA-3, suggesting a direct skewing toward Th2 differentiation without a Th0 intermediate. The hepatitis C virus envelope protein E2 is the only ligand known for CD81. Therefore, we propose that this new type of Ag-independent T cell activation may occur in hepatitis C virus-infected individuals, contributing to liver inflammation, impaired type 1 immune responses, and recurrent flares of type 2 immunity associated with chronic infection.
- Published
- 2008
- Full Text
- View/download PDF
30. Expression and selective up-regulation of toxin-related mono ADP-ribosyltransferases by pathogen-associated molecular patterns in alveolar epithelial cells.
- Author
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Balducci E, Micossi LG, Soldaini E, and Rappuoli R
- Subjects
- Animals, Arginine metabolism, Cell Line, Cricetinae, Cricetulus, Enzyme Activation drug effects, Epithelial Cells drug effects, Flagellin pharmacology, Gene Expression Regulation, Enzymologic drug effects, Humans, Lipopeptides, Lipopolysaccharides pharmacology, Peptides pharmacology, Peptidoglycan pharmacology, Pulmonary Alveoli drug effects, Pulmonary Alveoli enzymology, RNA, Messenger genetics, RNA, Messenger metabolism, Substrate Specificity drug effects, Teichoic Acids pharmacology, Up-Regulation drug effects, ADP Ribose Transferases genetics, ADP Ribose Transferases metabolism, Bacterial Toxins metabolism, Epithelial Cells enzymology, Epithelial Cells immunology, Pulmonary Alveoli cytology, Up-Regulation genetics
- Abstract
Mono ADP-ribosyltransferases (ARTs) are a family of enzymes related to bacterial toxins that possess adenosine diphosphate ribosyltransferase activity. We have assessed that A549 constitutively expressed ART1 on the cell surface and shown that lipotheicoic acid (LTA) and flagellin, but not lipopolysaccharide (LPS), peptidoglycan (PG) and poly (I:C), up-regulate ART1 in a time and dose dependent manner. These agonists did not alter the expression of ART3 and ART5 genes. Indeed, LTA and flagellin stimulation increased the level of ART1 protein and transcript while ART4 gene was activated after stimulation of cells with LPS, LTA, PAM and PG via TLR2 and TLR4 receptors. These results show that human ARTs possess a differential capacity to respond to bacteria cell wall components and might play a crucial role in innate immune response in airways.
- Published
- 2007
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- View/download PDF
31. T cell costimulation by the hepatitis C virus envelope protein E2 binding to CD81 is mediated by Lck.
- Author
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Soldaini E, Wack A, D'Oro U, Nuti S, Ulivieri C, Baldari CT, and Abrignani S
- Subjects
- Calcium Signaling drug effects, Cyclodextrins pharmacology, Humans, Jurkat Cells drug effects, Jurkat Cells immunology, Lymphocyte Specific Protein Tyrosine Kinase p56(lck) deficiency, Membrane Microdomains enzymology, Membrane Proteins metabolism, Neoplasm Proteins physiology, Phosphorylation, Receptor-CD3 Complex, Antigen, T-Cell physiology, Receptors, Antigen, T-Cell metabolism, Tetraspanin 28, Viral Envelope Proteins metabolism, Viral Envelope Proteins pharmacology, Antigens, CD physiology, Calcium Signaling physiology, Hepacivirus immunology, Lymphocyte Specific Protein Tyrosine Kinase p56(lck) physiology, Membrane Proteins physiology, Protein Processing, Post-Translational physiology, Viral Envelope Proteins immunology, beta-Cyclodextrins
- Abstract
Binding of the hepatitis C virus (HCV) envelope protein E2 to CD81 provides a costimulatory signal for human T cells. This phenomenon may play a role in liver damage and autoimmune manifestations associated with HCV infection. Here we show that cross-linking of CD81 by HCV E2 induced a calcium flux in T cells that depends on Lck since it was blocked by PP1 and absent in Lck-deficient Jurkat T cells. In wild-type Jurkat cells, Lck was activated by CD81 cross-linking, and CD81, like Lck, was found in lipid rafts. Indeed, the integrity of the raft compartment was required for the induction of a calcium flux by E2, since methyl-beta-cyclodextrin abolished this response. A requirement for TCR/CD3 expression was indicated by the absence of a calcium flux following E2 stimulation of TCR/CD3-deficient Jurkat cells. CD81 cross-linking increased and prolonged the anti-CD3-induced tyrosine phosphorylation of TCR1 and of other proteins, indicating that the CD81-mediated signal converges with the TCR/CD3 signaling cascade at its most upstream step. In conclusion, we propose that the costimulatory effects of HCV E2 on T cells depend on CD81 cross-linking that activates Lck through raft aggregation and thus leads to enhanced TCR signaling.
- Published
- 2003
- Full Text
- View/download PDF
32. Binding of the hepatitis C virus envelope protein E2 to CD81 provides a co-stimulatory signal for human T cells.
- Author
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Wack A, Soldaini E, Tseng C, Nuti S, Klimpel G, and Abrignani S
- Subjects
- CD28 Antigens physiology, CD3 Complex physiology, Cytokines biosynthesis, Humans, Interleukin-2 pharmacology, Receptors, Antigen, T-Cell physiology, Tetraspanin 28, Antigens, CD physiology, Hepatitis C immunology, Lymphocyte Activation, Membrane Proteins, T-Lymphocytes immunology, Viral Envelope Proteins physiology
- Abstract
Chronic hepatitis C virus (HCV) infection frequently develops into liver disease and is accompanied by extra-hepatic autoimmune manifestations. The tetraspanin CD81 is a putative HCV receptor as it binds the E2 envelope glycoprotein of HCV and bona fide HCV particles. Here we show that HCV E2 binding to CD81 on human cells in vitro lowers the threshold for IL-2 receptor alpha expression and IL-2 production, resulting in strongly increased T cell proliferation. HCV E2-induced co-stimulation also enhances the production of IFN-gamma and IL-4 and causes increased TCR down-regulation. This suggests that binding of HCV particles to CD81 on T cells in vivo may lead to activation by otherwise suboptimal stimuli. Therefore, co-stimulation of autoreactive T cells by HCV may contribute to liver damage and autoimmune phenomena observed in HCV infection.
- Published
- 2001
- Full Text
- View/download PDF
33. DNA binding site selection of dimeric and tetrameric Stat5 proteins reveals a large repertoire of divergent tetrameric Stat5a binding sites.
- Author
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Soldaini E, John S, Moro S, Bollenbacher J, Schindler U, and Leonard WJ
- Subjects
- Amino Acid Sequence, Animals, Base Sequence, Binding Sites, Cell Line, DNA genetics, DNA-Binding Proteins chemistry, DNA-Binding Proteins genetics, Humans, Molecular Sequence Data, Protein Binding, Protein Conformation, STAT5 Transcription Factor, Sequence Alignment, Signal Transduction, Trans-Activators chemistry, Trans-Activators genetics, Transcription, Genetic, Tumor Suppressor Proteins, DNA metabolism, DNA-Binding Proteins metabolism, Milk Proteins, Trans-Activators metabolism
- Abstract
We have defined the optimal binding sites for Stat5a and Stat5b homodimers and found that they share similar core TTC(T/C)N(G/A)GAA interferon gamma-activated sequence (GAS) motifs. Stat5a tetramers can bind to tandemly linked GAS motifs, but the binding site selection revealed that tetrameric binding also can be seen with a wide range of nonconsensus motifs, which in many cases did not allow Stat5a binding as a dimer. This indicates a greater degree of flexibility in the DNA sequences that allow binding of Stat5a tetramers than dimers. Indeed, in an oligonucleotide that could bind both dimers and tetramers, it was possible to design mutants that affected dimer binding without affecting tetramer binding. A spacing of 6 bp between the GAS sites was most frequently selected, demonstrating that this distance is favorable for Stat5a tetramer binding. These data provide insights into tetramer formation by Stat5a and indicate that the repertoire of potential binding sites for this transcription factor is broader than expected.
- Published
- 2000
- Full Text
- View/download PDF
34. The significance of tetramerization in promoter recruitment by Stat5.
- Author
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John S, Vinkemeier U, Soldaini E, Darnell JE Jr, and Leonard WJ
- Subjects
- Base Sequence, Binding Sites, Cell Line, Transformed, DNA metabolism, DNA-Binding Proteins genetics, Dimerization, Humans, Molecular Sequence Data, Mutagenesis, Response Elements, STAT5 Transcription Factor, Trans-Activators genetics, Transcriptional Activation, Tumor Suppressor Proteins, DNA-Binding Proteins metabolism, Milk Proteins, Promoter Regions, Genetic, Receptors, Interleukin-2 genetics, Trans-Activators metabolism
- Abstract
Stat5a and Stat5b are rapidly activated by a wide range of cytokines and growth factors, including interleukin-2 (IL-2). We have previously shown that these signal transducers and activators of transcription (STAT proteins) are key regulatory proteins that bind to two tandem gamma interferon-activated site (GAS) motifs within an IL-2 response element (positive regulatory region III [PRRIII]) in the human IL-2Ralpha promoter. In this study, we demonstrate cooperative binding of Stat5 to PRRIII and explore the molecular basis underlying this cooperativity. We demonstrate that formation of a tetrameric Stat5 complex is essential for the IL-2-inducible activation of PRRIII. Stable tetramer formation of Stat5 is mediated through protein-protein interactions involving a tryptophan residue conserved in all STATs and a lysine residue in the Stat5 N-terminal domain (N domain). The functional importance of tetramer formation is shown by the decreased levels of transcriptional activation associated with mutations in these residues. Moreover, the requirement for STAT protein-protein interactions for gene activation from a promoter with tandemly linked GAS motifs can be relieved by strengthening the avidity of protein-DNA interactions for the individual binding sites. Taken together, these studies demonstrate that a dimeric but tetramerization-deficient Stat5 protein can activate only a subset of target sites. For functional activity on a wider range of potential recognition sites, N-domain-mediated oligomerization is essential.
- Published
- 1999
- Full Text
- View/download PDF
35. The cis-acting elements controlling mouse IL-2R alpha transcription.
- Author
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Nabholz M, Soldaini E, Sperisen P, Pla M, Wang SM, MacDonald HR, Reichenbach P, Beermann F, and Bucher P
- Subjects
- Animals, Mice, Gene Expression Regulation immunology, Receptors, Interleukin-2 genetics, Regulatory Sequences, Nucleic Acid immunology, Transcription, Genetic immunology
- Published
- 1995
- Full Text
- View/download PDF
36. Enhancement of plasma levels of tumor necrosis factor alpha but not interleukin-6 following endotoxin injection of Friend leukemia virus infected mice.
- Author
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Soldaini E, Baldinotti F, Matteucci D, Specter S, and Bendinelli M
- Subjects
- Animals, Female, Kinetics, Lipopolysaccharides toxicity, Mice, Mice, Inbred BALB C, Tumor Necrosis Factor-alpha antagonists & inhibitors, Friend murine leukemia virus, Interleukin-6 blood, Leukemia, Experimental immunology, Retroviridae Infections immunology, Tumor Necrosis Factor-alpha biosynthesis, Tumor Virus Infections immunology
- Abstract
Friend leukemia virus complex (FLC) infection of BALB/c mice causes a rapid, progressive suppression of most immune functions. In the present study, FLC infection resulted in increased induction by bacterial lipopolysaccharide (LPS) of tumor necrosis factor alpha (TNF alpha) but not IL-6. TNF alpha levels were significantly elevated beginning 11 days post infection and increasing levels were measured through day 21. The highest TNF alpha levels in FCL-infected mice were as much as 100-fold higher than in LPS treated non-infected mice. Peak plasma levels of TNF alpha were seen between 1 and 2 hr after LPS induction, as compared to a peak at 1 hr in controls. The ability of LPS to stimulate TNF alpha was concentration dependent over a range of 0.005 to 50 micrograms per mouse. Using anti-TNF alpha antiserum, cytotoxic activity of plasma was shown to be due specifically to TNF alpha. These data suggest that induction of TNF alpha and IL-6 is regulated by different mechanisms in FLC-infected mice.
- Published
- 1994
37. Minimal growth requirements of mature T lymphocytes: interleukin (IL)-1 and IL-6 increase growth rate but not plating efficiency of CD4 cells stimulated with anti-CD3 and IL-2.
- Author
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Soldaini E, MacDonald HR, and Nabholz M
- Subjects
- Animals, CD3 Complex, CD4-Positive T-Lymphocytes physiology, CD8 Antigens analysis, Female, Mice, Mice, Inbred C57BL, T-Lymphocytes drug effects, T-Lymphocytes physiology, Antibodies, Monoclonal immunology, Antigens, Differentiation, T-Lymphocyte immunology, CD4-Positive T-Lymphocytes drug effects, Interleukin-1 pharmacology, Interleukin-2 physiology, Interleukin-6 pharmacology, Receptors, Antigen, T-Cell immunology
- Abstract
We show that interleukin (IL)-2 is necessary and sufficient for the proliferation of both CD4 and CD8 subsets of peripheral murine T cells activated by plastic-bound anti-CD3 monoclonal antibodies (mAb). The frequency of proliferating cells (f) was 0.32 for CD4 cells and 0.63 for CD8 cells. These frequencies were not increased by the addition of IL-1 or IL-6, alone or in combination. These cytokines were unable to induce responsiveness to IL-2 in T cells confirming that they cannot substitute for the signal delivered via the TcR/CD3 complex. On the other hand, IL-1 and IL-6 increase the growth rate of CD4 cells. The addition of IL-6 significantly lowered the mean doubling time (dt) of CD4 cells (dt: 26 h vs. 38 h in the presence of IL-2 alone, p less than 0.01), while the addition of IL-1, ineffective by itself, combined with IL-6 further increased the growth rate of CD4 cells (dt: 23 h, p less than 0.001). The growth rate of CD8 cells stimulated with anti-CD3 and IL-2, was markedly faster than that of CD4 cells (dt: 18 h vs. 38 h, p less than 0.001) and was not significantly influenced by addition of IL-1 and/or IL-6.
- Published
- 1992
- Full Text
- View/download PDF
38. Alterations of T-cell functions during Friend leukemia complex infection: defective signal transduction?
- Author
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Soldaini E, Matteucci D, Capobianchi MR, Baldinotti F, Giovannetti A, Dianzani F, and Bendinelli M
- Subjects
- Animals, Calcimycin pharmacology, Concanavalin A pharmacology, Filtration, Fluorescent Antibody Technique, Immunophenotyping, Interferon-gamma biosynthesis, Interleukin-2 biosynthesis, Interleukin-2 pharmacology, Mice, Mice, Inbred BALB C, T-Lymphocytes drug effects, Tetradecanoylphorbol Acetate pharmacology, Friend murine leukemia virus immunology, Leukemia, Experimental immunology, Lymphocyte Activation immunology, Signal Transduction immunology, T-Lymphocytes immunology
- Abstract
Proliferative and interleukin responses to T-cell mitogens such as concanavalin A (Con A) were rapidly and progressively reduced in BALB/c mice infected with the Friend leukemia complex (FLC) or its helper, Friend murine leukemia virus (F-MuLV). In contrast, a combination of the protein kinase C activator phorbol ester 12-O-tetradecanoylphorbol 13-acetate (TPA) and the Ca++ ionophore A23187 elicited a normal lymphoproliferative response up to 8 days postinfection (p.i.) and normal interleukin-2 (IL-2) and interferon-gamma responses up to day 14 p.i. Exogenous IL-2 failed to restore the lymphoproliferative response of infected cells regardless of the stimulation used. These results showed that the T-cell deficits may be at least partly attributable to a derangement of the signal transduction pathway leading to activation. Spleen cells passed through nylon wool columns reacquired a normal responsiveness to Con A +/- TPA up to 14 days p.i. The latter finding suggests that the alterations in signal transduction are not caused by primary defect of the responder-T cells but may result from an extrinsic suppressive mechanism.
- Published
- 1991
- Full Text
- View/download PDF
39. Role of interferon in lethality and lymphoid atrophy induced by Coxsackievirus B3 infection in mice.
- Author
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Capobianchi MR, Matteucci D, Giovannetti A, Soldaini E, Bendinelli M, Stanton JG, and Dianzani F
- Subjects
- Animals, Disease Models, Animal, Immunosuppression Therapy, Interferon-alpha analysis, Interferon-alpha immunology, Interferon-alpha pharmacology, Interferon-beta analysis, Interferon-beta immunology, Interferon-beta pharmacology, Lymphoid Tissue drug effects, Mice, Mice, Inbred BALB C, Spleen pathology, Survival physiology, Coxsackievirus Infections pathology, Enterovirus B, Human pathogenicity, Interferons analysis, Interferons immunology, Interferons pharmacology, Lymphoid Tissue pathology
- Abstract
To assess the importance of interferon (IFN) in the pathology of coxsackievirus B3 (CVB-3) infection, we evaluated both mortality rate and lymphoid involution in young adult BALB/C mice infected with lethal doses of the virus and treated either with anti-IFN antibody or with murine IFN-alpha/beta. Administration of antibody to IFN caused a profound worsening of the pathology and an increase in the mortality rate in infected animals. Treatment with murine IFN exerted a significant ameliorative effect on lethality when administered concomitantly with or soon after virus infection. The extent of this protection was correlated with the plasma levels of exogenous or endogenous IFN at 6 h postinfection, whereas no correlation with IFN titers was found later. The effects of IFN apparently were not directly mediated by antiviral effects, because at the times studied, no relation was found between IFN levels and virus titers, at least in the plasma of the infected animals. Lymphoid atrophy, assessed by measuring spleen weight, was only partially reversed by early IFN treatment. These data suggest that IFN production is critical during the early phases of infection, whereas it does not seem to play a significant protective role at later stages.
- Published
- 1991
- Full Text
- View/download PDF
40. Friend leukemia complex infection of mice as an experimental model for AIDS studies.
- Author
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Soldaini E, Matteucci D, Lopez-Cepero M, Specter S, Friedman H, and Bendinelli M
- Subjects
- Animals, Friend murine leukemia virus immunology, Humans, Interleukins biosynthesis, Leukemia, Experimental prevention & control, Leukemia, Experimental therapy, Lymphocytes immunology, Mice, Acquired Immunodeficiency Syndrome immunology, Disease Models, Animal, Immune Tolerance, Leukemia, Experimental immunology
- Abstract
It is now clear that AIDS results from a complex pathogenesis where virus-induced cytopathology represents only one of the contributing factors, while the others remain elusive. For this and other reasons there is much interest in the mechanisms whereby other classically immunodepressive noncytocidal retroviruses, such as viruses of the murine Friend leukemia complex (FLC), affect the immune system. FLC-induced immunosuppression has already provided important leads to the understanding of the mechanisms whereby retroviruses immunosuppress their hosts. It is expected that further investigation of the model will prove useful in several areas of AIDS research, including the development of efficacious drug therapies.
- Published
- 1989
- Full Text
- View/download PDF
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