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Multiple sclerosis (MS) is a chronic demyelinating autoimmune disease that affects the central nervous system (CNS), varying from relatively benign to severely disabling. Although the roles of several cytokines and chemokines in MS are well established, their roles in MS lesions and evolution remain a matter of debate. Soluble CD40L (sCD40L) is a ligand that induces lymphocyte proinflammatory activity by stimulating the activation and maturation of B cells, promoting isotype switching and affinity hypermutation. Circulating sCD40L levels reflect activation of the CD40-CD40L complex. The interaction between CD40 and CD40L is of fundamental importance, suggesting their role in MS pathogenesis. Interleukin-31 (IL-31) is a proinflammatory cytokine that plays a role in allergies, autoimmune diseases, and is a major factor in several chronic inflammatory diseases. IL-31 triggers the JAK-STAT pathway in several different cell types, to induce proliferation and tissue remodeling in fibroblasts, epithelial cells, and endothelial cells. Some studies have described a correlation between these two cytokines and decreased serum levels of sCD40L and IL-31 after MS treatment, accompanied by a lower inflammatory response. In this review, we emphasize the possible correlation and positive feedback between IL31 and sCD40L in the MS proinflammatory response. We also describe the justification for this hypothesis and whether it is possible to investigate these cytokines as biomarkers of MS.

Mesenchymal stem cells comprise a natural reservoir of undifferentiated cells within adult tissues. Given their self-renewal, multipotency, regenerative potential and immunomodulatory properties, MSCs have been reported as a promising cell therapy for the treatment of different diseases, including neurodegenerative and autoimmune diseases. In this study, we investigated the immunomodulatory properties of human tubal mesenchymal stem cells (htMSCs) using the EAE model. htMSCs were able to suppress dendritic cells activation downregulating antigen presentation-related molecules, such as MHCII, CD80 and CD86, while impairing IFN-γ and IL-17 and increasing IL-10 and IL-4 secretion. It further correlated with milder disease scores when compared to the control group due to fewer leukocytes infiltrating the CNS, specially Th1 and Th17 lymphocytes, associated with increased IL-10 secreting Tr1 cells. Conversely, microglia were less activated and infiltrating mononuclear cells secreted higher levels of IL-4 and IL-10 and expressed reduced chemokine receptors as CCR4, CCR6 and CCR8. qPCR of the spinal cords revealed upregulation of indoleamine-2,3-dioxygenase (IDO) and brain derived neurotrophic factor (BDNF). Taken together, here evidenced the potential of htMSCs as an alternative for the treatment of inflammatory, autoimmune or neurodegenerative diseases.

Multiple sclerosis is a chronic and demyelinating disease of the central nervous system (CNS), most prevalent in women, and with an important social and economic cost worldwide. It is triggered by self-reacting lymphocytes that infiltrate the CNS and initiate neuroinflammation. Further, axonal loss and neuronal death takes place, leading to neurodegeneration and brain atrophy. The murine model for studying MS, experimental autoimmune encephalomyelitis (EAE), consists in immunizing mice with myelin-derived epitopes. APCs activate encephalitogenic T CD4 and CD8 lymphocytes that migrate mainly to the spinal cord resulting in neuroinflammation. Most of the knowledge on the pathophysiology and treatment of MS was obtained from EAE experiments, as Th17 cells, anti-alpha4 blocking Abs and the role of microbiota. Conversely, recent technology breakthroughs, such as CyTOF and single-cell RNA-seq, promise to revolutionize our understanding on the mechanisms involved both in MS and EAE. In fact, the importance of specific cellular populations and key molecules in MS/EAE is a constant matter of debate. It is well accepted that both Th1 and Th17 T CD4 lymphocytes play a relevant role in disease initiation after re-activation in situ. What is still under constant investigation, however, is the plasticity of the lymphocyte population, and the individual contribution of both resident and inflammatory cells for the progression or recovery of the disease. Thus, in this review, new findings obtained after single-cell analysis of blood and central nervous system infiltrating cells from MS/EAE and how they have contributed to a better knowledge on the cellular and molecular mechanisms of neuroinflammation are discussed.

Mesenchymal stem cells comprise a natural reservoir of undifferentiated cells within adult tissues. Given their self-renewal, multipotency, regenerative potential and immunomodulatory properties, MSCs have been reported as a promising cell therapy for the treatment of different diseases, including neurodegenerative and autoimmune diseases. In this study, we investigated the immunomodulatory properties of human tubal mesenchymal stem cells (htMSCs) using the EAE model. htMSCs were able to suppress dendritic cells activation downregulating antigen presentation-related molecules, such as MHCII, CD80 and CD86, while impairing IFN-γ and IL-17 and increasing IL-10 and IL-4 secretion. It further correlated with milder disease scores when compared to the control group due to fewer leukocytes infiltrating the CNS, specially Th1 and Th17 lymphocytes, associated with increased IL-10 secreting Tr1 cells. Conversely, microglia were less activated and infiltrating mononuclear cells secreted higher levels of IL-4 and IL-10 and expressed reduced chemokine receptors as CCR4, CCR6 and CCR8. qPCR of the spinal cords revealed upregulation of indoleamine-2,3-dioxygenase (IDO) and brain derived neurotrophic factor (BDNF). Taken together, here evidenced the potential of htMSCs as an alternative for the treatment of inflammatory, autoimmune or neurodegenerative diseases.

NLRP3 inflammasome [NLR (nucleotide-binding domain, leucine-rich repeat containing protein) Pyrin-domain-containing 3 ] functions as an innate sensor of several PAMPs and DAMPs (pathogen- and damage-associated molecular patterns). It has been also reported as a transcription factor related to Th2 pattern, although its role in the adaptive immunity has been controversial, mainly because the studies were performed using gene deletion approaches. In the present study, we have investigated the NLRP3 gain-of-function in the context of encephalomyelitis autoimmune disease (EAE), considered to be a Th1- and Th17-mediated disease. We took advantage of an animal model with NLRP3 gain-of-function exclusively to T CD4+ lymphocytes (CD4CreNLRP3fl/fl). These mice presented reduced clinical score, accompanied by less infiltrating T CD4+ cells expressing both IFN-γ and IL-17 at the central nervous system (CNS) during the peak of the disease. However, besides NLRP3 gain-of-function in lymphocytes, these mice lack NLRP3 expression in non-T CD4+ cells. Therefore, in order to circumvent this deficiency, we transferred naive CD4+ T cells from WT, NLRP3−/− or CD4CreNLRP3fl/fl into Rag-1−/− mice and immunized them with MOG35–55. Likewise, the animals repopulated with CD4CreNLRP3fl/fl T CD4+ cells presented reduced clinical score and decreased IFN-γ production at the peak of the disease. Additionally, primary effector CD4+ T cells derived from these mice presented reduced glycolytic profile, a metabolic profile compatible with Th2 cells. Finally, naive CD4+ T cells from CD4CreNLRP3fl/fl mice under a Th2-related cytokine milieu cocktail exhibited in vitro an increased IL-4 and IL-13 production. Conversely, naive CD4+ T cells from CD4CreNLRP3fl/fl mice under Th1 differentiation produced less IFN-γ and T-bet. Altogether, our data evidence that the NLRP3 gain-of-function promotes a Th2-related response, a pathway that could be better explored in the treatment of multiple sclerosis.

Neuromyelitis Optica Spectrum Disorder (NMOSD) is characterized as an autoimmune, inflammatory and demyelinating disease of the Central Nervous System (CNS). Its pathogenesis is due to the presence of anti-aquaporin 4 immunoglobulin G1 antibodies (anti-AQP4IgG), with presence of lymphocytes T Helper 1 and 17 (TH1 and TH17), in addition to previous neuroinflammation. The Mast cell (MC) is a granular cell present in all vascularized tissues, close to vessels, nerves, and meninges. In CNS, MCs are in the area postrema, choroid plexus, thalamus and hypothalamus. MC has ability to transmigrate between the nervous tissue and the lymphoid organs, interacting with the cells of both systems. These cells reach the CNS during development through vessel migration. Most MCs reside on the abluminal side of the vessels, where it can communicate with neurons, glial cells, endothelial cells and the extracellular matrix. Considering the role of MCs in neurodegenerative diseases has been extensively discussed, we hypothesized MCs participate in the pathogenesis of NMOSD. This cell represents an innate and adaptive immune response regulator, capable of faster responses than microglial cells. The study of MCs in NMOSD can help to elucidate the pathogenesis of this disease and guide new research for the treatment of patients in the future. We believe this cell is an important component in the cascade of NMOSD neuroinflammation.

Made available in DSpace on 2021-06-25T11:03:38Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-05-01 Cellular therapy with mesenchymal stem cells (MSCs) is a huge challenge for scientists, as little translational relevance has been achieved. However, many studies using MSCs have proved their suppressive and regenerative capacity. Thus, there is still a need for a better understanding of MSCs biology and the establishment of newer protocols, or to test unexplored tissue sources. Here, we demonstrate that murine endometrial-derived MSCs (meMSCs) suppress Experimental Autoimmune Encephalomyelitis (EAE). MSC-treated animals had milder disease, with a significant reduction in Th1 and Th17 lymphocytes in the lymph nodes and in the central nervous system (CNS). This was associated with increased Il27 and Cyp1a1 expression, and presence of IL-10-secreting T CD4+ cells. At EAE peak, animals had reduced CNS infiltrating cells, histopathology and demyelination. qPCR analysis evidenced the down-regulation of several pro-inflammatory genes and up-regulation of indoleamine-2,3-dioxygenase (IDO). Consistently, co-culturing of WT and IDO-/- meMSCs with T CD4+ cells evidenced the necessity of IDO on the suppression of encephalitogenic lymphocytes, and IDO-/- meMSCs were not able to suppress EAE. In addition, WT meMSCs stimulated with IL-17A and IFN-γ increased IDO expression and secretion of kynurenines in vitro, indicating a negative feedback loop. Pathogenic cytokines were increased when CD4+ T cells from AhR-/- mice were co-cultured with WT meMSC. In summary, our research evidences the suppressive activity of the unexplored meMSCs population, and shows the mechanism depends on IDO-kynurenines-Aryl hydrocarbon receptor (AhR) axis. To our knowledge this is the first report evidencing that the therapeutic potential of meMSCs relying on IDO expression. Neuroimmune Interactions Laboratory Department of Immunology University of São Paulo (USP) Immunopathology and Allergy Post Graduate Program School of Medicine University of São Paulo (USP) Institute of Biosciences UNESP Clinical Biochemistry Laboratory Clinical Analysis Department University of São Paulo (USP) Department of Immunology Institute of Biomedical Sciences University of São Paulo (USP) Division of Reproductive Medicine Célula Mater Division of Reproductive Medicine Halpern Clinic Division of Reproductive Medicine CEERH Institute of Biosciences UNESP

Zika virus (ZIKV) is a mosquito-borne Flavivirus structurally and antigenically related to Dengue virus (DENV). Zika virus has been associated with congenital anomalies and most ZIKV outbreaks have occurred in endemic areas of DENV. The present study investigated the effects of prior DENV serotype 1 (DENV1) immunity in immunocompetent female Swiss mice on gestational ZIKV infection in offspring. Physical/reflex development, locomotor activity, anxiety, visual acuity, and brain-derived neurotrophic factor (BDNF) levels were evaluated in offspring during infancy and adolescence. Anti-DENV1 and anti-ZIKV antibodies were detected in sera of the progenitors, whereas no ZIKV genomes were detected in the offspring brain. Pups from dams with only DENV1 immunity presented alterations of physical/reflex development. Pups from all infected dams exhibited time-related impairments in locomotor activity and anxiolytic-like behavior. Offspring from DENV/ZIKV-infected dams exhibited impairments in visual acuity during infancy but not during adolescence, which was consistent with morphometric analysis of the optic nerve. Pups from DENV1-, ZIKV-, and DENV/ZIKV-infected dams exhibited a decrease in BDNF levels during infancy and an increase during adolescence in distinct brain regions. In summary, we found no influence of prior DENV1 immunity on gestational ZIKV infection in offspring, with the exception of alterations of early visual parameters, and an increase in BDNF levels in the hippocampus during adolescence.

Multiple sclerosis (MS) is an autoimmune and neuroinflammatory disease characterized by demyelination of the Central Nervous System. Immune cells activation and release of pro-inflammatory cytokines play a crucial role in the disease modulation, decisively contributing to the neurodegeneration observed in MS and the experimental autoimmune encephalomyelitis (EAE), the widely used MS animal model. Synthetic glucocorticoids, commonly used to treat the MS attacks, have controversial effects on neuroinflammation and cognition. We sought to verify the influence of dexamethasone (DEX) on the EAE progression and on EAE-induced cognitive deficits. In myelin oligodendrocyte glycoprotein peptide (MOG35-55)-induced EAE female mice, treated once with DEX (50 mg/kg) or not, on the day of immunization, DEX decreased EAE-induced motor clinical scores, infiltrating cells in the spinal cord and delayed serum corticosterone peak. At the asymptomatic phase (8-day post-immunization), DEX did not protected from the EAE-induced memory consolidation deficits, which were accompanied by increased glucocorticoid receptor (GR) activity and decreased EGR-1 expression in the hippocampus. Blunting hippocampal GR genomic activation with DnGR vectors prevented DEX effects on EAE-induced memory impairment. These data suggest that, although DEX improves clinical signs, it decreases cognitive and memory capacity by diminishing neuronal activity and potentiating some aspects of neuroinflammation in EAE.

MicroRNAs (miRNAs) are a family of non-translated small ribonucleic acids (RNAs) measuring 21–25 nucleotides in length that play various roles in multiple sclerosis (MS). By regulating gene expression via either mediating translational repression or cleavage of the target RNA, miRNAs can alter the expression of transcripts in different cells, such as B lymphocytes, also known as B cells. They are crucial in the pathogenesis of MS; however, they have not been extensively studied during the treatment of some drugs such as natalizumab (NTZ). NTZ is a humanized immunoglobulin G4 antibody antagonist for integrin alpha 4 (α4) used in the treatment of MS. The drug reduces the homing of lymphocytes to inflammation sites. Integrin α4 expression on the cell surface of B cells is related to MS severity, indicating a critical component in the pathogenesis of the disease. NTZ plays an important role in modifying the gene expression in B cells and the levels of miRNAs in the treatment of MS. In this review, we have described changes in gene expression in B cells and the levels of miRNAs during NTZ therapy in MS and its relapse. Studies using the experimental autoimmune encephalomyelitis (EAE) model and those involving patients with MS have described changes in the levels of microRNAs in the regulation of proteins affected by specific miRNAs, gene expression in B cells, and certain functions of B cells as well as their subpopulations. Therefore, there is a possibility that some miRNAs could be studied at different stages of MS during NTZ treatment, and these specific miRNAs can be tested as markers of therapeutic response to this drug in future studies. Physiopathology, gene expression in B cells and their subpopulations can help understand this complex puzzle involving miRNAs and the therapeutic response of patients with MS., MicroRNA; Natalizumab; Multiple sclerosis; B lymphocyte; Therapy.

Introduction Multiple Sclerosis (MS) is a chronic, autoimmune, demyelinating disease of the central nervous system (CNS). Currently, several protocols are described for the different phases of MS. In this longitudinal study, we aim to quantify the concentration of plasma cytokines of MS patients treated with Fingolimod alone or after Glatiramer Acetate (GA) or Interferon-beta (IFN-β), in order to compeer both treatments and describes if it is possible to use them as biomarkers. Objective Compare the two different types of drug treatment and describes possible immune biomarkers in RRMS patients treated with Fingolimod alone or after GA or IFN-β. Materials and methods This is a controlled, non-randomized clinical trial. Plasma concentrations of IL-31, sCD40L and nine others cytokines were evaluated in two groups of patients with a one-year follow-up. Group 1 (n = 12): RRMS patients treated with GA or IFN-β for at least six months before the study who changed therapy to Fingolimod after six months, and Group 2 (n = 12): naive RRMS patients who started treatment with Fingolimod. We used ANOVA two-way to analyze the cytokines and Spearman coefficient to evaluate the correlation. Results Although Group 2 started with a greater number of relapses per disease duration, Fingolimod treatment was effective in decreasing this parameter, as well as EDSS over 12 months. However, the treatment with GA or IFN-β on Group 1 showed a tendency to increase the number of relapses after 6 months of follow-up, which decrease when the therapy was changed to Fingolimod. After the evaluation of 11 cytokines in one year, we found that IL-31 and sCD40L were the biomarkers that demonstrated a more difference when compared to the classical ones, following the clinical pattern over the treatment period. Conclusions Our study describes the existence of two promising plasmatic biomarkers (IL-31 and sCD40L), which reduced plasmatic levels in RRMS patients followed the treatment time of Fingolimod, despite that more studies are needed to prove their efficiency.

Viral infections have always been the cause of serious human diseases, usually increasing rates of morbidity and mortality worldwide. In 2015, the flavivirus Zika virus (ZIKV) caused an alarming increase in the number of babies born with microcephaly. Genetic differences, mainly related to immune response, are known to influence susceptibility to infection, once is very important in blocking viral replication and may be modulated by several different factors, in which, miRNAs play a key role. Still very little is known about the involvement of miRNAs during ZIKV infection. In this context, we evaluated the role of miRNAs during ZIKV experimental infection. We performed miRNAs analysis in vitro using CNS cells and, in vivo, with SJL animals susceptible to infection. Analyzing human neurons, we observed that ZIKV was able to reduce miR-9 and this reduction is known to cause cerebral cortex thickness reduction and ventriculomegaly, characteristics similar to microcephaly. In human neuronal precursor cells, ZIKV was able to reduce miR-194, miR-302b and miR-302c expression and consequently increased MXD1, a transcriptional repressor. On the other hand, ZIKV infection increased miR-295 and miR-302d expression leading to a reduction of AHR repressor and molecules involved in neurodevelopment, neuroD4, and neuroD6. In SJL fetal brain a miR-146 increase leading a decrease of IRAK1, favoring viral replication. Taken together, these data are indicative that ZIKV is able to modulate miRNA profile to regulate important molecules involved in neurodevelopment and antiviral immune response, evidencing the importance of these regulatory molecules, which may help us to better understand immunopathogenic mechanisms of microcephaly caused by ZIKV

The wake-promoting drug Modafinil has been used for treatment of sleep disorders, such as Narcolepsy, excessive daytime sleepiness and sleep apnea, due to its stimulant action. Despite the known effect of Modafinil on brain neurochemistry, particularly on brain dopamine system, recent evidence support an immunomodulatory role for Modafinil treatment in neuroinflammatory models. Here, we aimed to study the effects of in vitro and in vivo Modafinil treatment on activation, proliferation, cell viability, and cytokine production by immune cells in splenocytes culture from mice. The results show that in vitro treatment with Modafinil increased Interferon (IFN)-γ, Interleukin (IL)-2 and IL-17 production and CD25 expression by T cells. In turn, in vivo Modafinil treatment enhanced splenocyte production of IFN-γ, IL-6 and tumor necrosis factor (TNF), and increased the number of IFN-γ producing cells. Next, we addressed the translational value of the observed effects by testing PBMCs from Narcolepsy type 1 patients that underwent Modafinil treatment. We reported increased number of IFN-γ producing cells in PBMCs from Narcolepsy type 1 patients following continuous Modafinil treatment, corroborating our animal data. Taken together, our results show, for the first time, a pro-inflammatory action of Modafinil, particularly on IFN-mediated immunity, in mice and in patients with Narcolepsy type 1. The study suggests a novel effect of this drug treatment, which should be taken into consideration when given concomitantly with an ongoing inflammatory or autoimmune process.

O Acidente vascular cerebral é uma doença aguda neuroinflamatória cuja prevalência aumentou nos últimos anos. Seus sintomas são decorrente da morte neuronal provocada pela privação de glicose e oxigênio. Após a morte neuronal, há liberação de citocinas, radicais livres e neurotransmissores, dentre eles o glutamato. Nosso objetivo é averiguar como o glutamato através do seu receptor NMDA modula a resposta inflamatória tanto de células residentes do SNC, quanto de células imunes infiltrantes. Para a realização desse estudos, realizamos experimentos in vitro e in vivo com o bloqueador do NMDAr, sob o processo de hipóxia. Nossos resultados demonstraram que a sinalização por NMDAr modula a expressão de moléculas envolvidas na apresentação de antígeno em células da microglia e macrófagos, bem como na produção de óxido nítrico por neutrófilos. O seu bloqueio diminui morte celular e lesão cerebral. Por fim, nossa pesquisa mostra que a sinalização NMDAr está envolvido não só com excitotoxicidade, mas também com a modulação da resposta da células inata. Stroke is an acute neuroinflammatory disease whose prevalence has increased in recent years. Its symptoms are due to the neuronal death caused by the deprivation of glucose and oxygen. After neuronal death, there is release of cytokines, free radicals and neurotransmitters, among them glutamate. Our goal is to investigate how glutamate through its NMDA receptor modulates the inflammatory response of both resident CNS cells and infiltrating immune cells. For the accomplishment of these studies, we performed experiments in vitro and in vivo with the NMDAr blocker under the hypoxia process. Our results demonstrated that NMDAr signaling modulates the expression of molecules involved in the presentation of antigen in microglia and macrophages cells, as well as in the production of nitric oxide by neutrophils. Its blockage decreases cell death and brain damage. Finally, our research shows that NMDAr signaling is involved not only with excitotoxicity, but also with the modulation of the innate cell response.

Stem cells from human exfoliated deciduous teeth (SHED) have great therapeutic potential and here, by the first time, we evaluated their immunomodulatory effect on experimental model of autoimmune encephalomyelitis (EAE). Specifically, we investigated the effect of SHED administration on clinical signs and cellular patterns in EAE model using Foxp3 GFP + transgenic mice (C57Bl/6-Foxp3GFP). The results showed that SHED infusion ameliorated EAE clinical score with reduced number of infiltrating IFN-γ+CD8+, IL-4+CD8+, IFN-γ+CD4+ and IL-4+CD4+ T cells into the central nervous system (CNS). In addition, we observed that SHED promoted a significant increase in CD4+FOXP3+ T cells population in the spleen of EAE-affected animals. Taken together, our results provide strong evidence that SHED can modulate peripherally the CD4+ T cell responses suggesting that SHED would be explored as part of cellular therapy in autoimmune diseases associated with CNS.

We present a case of microcephaly associated with Zika virus (ZIKV) in a chronological, multimodal imaging approach, illustrating the hallmarks of this disease on intrauterine morphological ultrasound, transfontanelar ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). We also determined the serological e immunological status of the mother and newborn. Noticeably, there was evidence for maternal infection by ZIKV, cytomegalovirus (CMV), herpes simplex virus (HSV), dengue virus (DENV) and Toxoplasma gondii, which indicates a possible role of previous exposures to STORCH agents and possibly comorbidities in the severe fetal congenital manifestation.Author SummaryZika virus (ZIKV) is an emerging mosquito-borne arbovirus causing dengue-like symptoms. In humans the illness is characterized by malaise and cutaneous rash and absent or short-termed fever. Recently, the Brazilian Ministry of Health reported an outbreak of microcephaly in Brazil as a delayed effect of the 2014-2015 outbreak of ZIKV in the Northeast of Brazil. A 20-fold increase in the notifications of newborns with microcephaly was documented during the second semester of 2015. This increase was almost immediately found to be associated with ZIKV infections, both in Brazil and, retrospectively, in French Polynesia. Herein we report a case of microcephaly associated with ZIKV and we also present evidence of other maternal infections. Our results indicated that, both mother and microcephaly infant had immunologic status compatible with previous exposure (in the mother) by STORCH agents. These indicate a possible role of previous exposures and possibly comorbidities in the severe fetal congenital manifestation. □

Our understanding of how thymocytes differentiate into many subtypes has been increased progressively in its complexity. At early life, the thymus provides a suitable microenvironment with specific combination of stromal cells, growth factors, cytokines, and chemokines to induce the bone marrow lymphoid progenitor T-cell precursors into single-positive CD4+and CD8+T effectors and CD4+CD25+T-regulatory cells (Tregs). At postthymic compartments, the CD4+T-cells acquire distinct phenotypes which include the classical T-helper 1 (Th1), T-helper 2 (Th2), T-helper 9 (Th9), T-helper 17 (Th17), follicular helper T-cell (Tfh), and induced T-regulatory cells (iTregs), such as the regulatory type 1 cells (Tr1) and transforming growth factor-β- (TGF-β-) producing CD4+T-cells (Th3). Tregs represent only a small fraction, 5–10% in mice and 1-2% in humans, of the overall CD4+T-cells in lymphoid tissues but are essential for immunoregulatory circuits mediating the inhibition and expansion of all lineages of T-cells. In this paper, we first provide an overview of the major cell-intrinsic developmental programs that regulate T-cell lineage fates in thymus and periphery. Next, we introduce the SV40 immortomouse as a relevant mice model for implementation of new approaches to investigate thymus organogenesis, CD4 and CD8 development, and thymus cells tumorogenesis.

SUMMARYLeishmania(L.)amazonensis[L.(L.)amazonensis] is widely distributed in Brazil and its symptomatic infections usually lead to few localized lesions and sometimes to diffuse cutaneous form, with nodules throughout the body, anergy to parasite antigens and poor therapeutic response. The variability of these manifestations draws attention to the need for studies on the pathophysiology of infection by this species. In this study, we analysed the course and immunological aspects ofL.(L.)amazonensisinfection in BALB/c and C57BL/6 strains, both susceptible, but displaying different clinical courses, and athymic BALB/c nude, to illustrate the role of T cell dependent responses. We analysed footpad thickness and parasite burden byin vivoimaging. Furthermore, we evaluated the cellular profile and cytokine production in lymph nodes and the inflammatory infiltrates of lesions. Nude mice showed delayed lesion development and less inflammatory cells in lesions, but higher parasite burden than BALB/c and C57BL/6. BALB/c and C57BL/6 mice had similar parasite burdens, lesion sizes and infiltrates until 6 weeks after infection, and after that C57BL/6 mice controlled the infection. Small differences in parasite numbers were observed in C57BL/6 macrophagesin vitro, indicating thatin vivomilieu accounts for most differences in infection. We believe our results shed light on the role of host immune system in the course ofL.(L.)amazonensisinfection by comparing three mouse strains that differ in parasitaemia and inflammatory cells.

Zika virus (ZIKV) is an arbovirus belonging to the genus Flavivirus (family Flaviviridae) and was first described in 1947 in Uganda following blood analyses of sentinel Rhesus monkeys. Until the twentieth century, the African and Asian lineages of the virus did not cause meaningful infections in humans. However, in 2007, vectored by Aedes aegypti mosquitoes, ZIKV caused the first noteworthy epidemic on the Yap Island in Micronesia. Patients experienced fever, skin rash, arthralgia and conjunctivitis. From 2013 to 2015, the Asian lineage of the virus caused further massive outbreaks in New Caledonia and French Polynesia. In 2013, ZIKV reached Brazil, later spreading to other countries in South and Central America. In Brazil, the virus has been linked to congenital malformations, including microcephaly and other severe neurological diseases, such as Guillain-Barre syndrome. Despite clinical evidence, direct experimental proof showing that the Brazilian ZIKV (ZIKV(BR)) strain causes birth defects remains absent. Here we demonstrate that ZIKV(BR) infects fetuses, causing intrauterine growth restriction, including signs of microcephaly, in mice. Moreover, the virus infects human cortical progenitor cells, leading to an increase in cell death. We also report that the infection of human brain organoids results in a reduction of proliferative zones and disrupted cortical layers. These results indicate that ZIKV(BR) crosses the placenta and causes microcephaly by targeting cortical progenitor cells, inducing cell death by apoptosis and autophagy, and impairing neurodevelopment. Our data reinforce the growing body of evidence linking the ZIKV(BR) outbreak to the alarming number of cases of congenital brain malformations. Our model can be used to determine the efficiency of therapeutic approaches to counteracting the harmful impact of ZIKV(BR) in human neurodevelopment.

Modafinil is a psychostimulant drug that is used to treat Narcolepsy and Excessive Daytime Sleepiness, due to a dopamine-related action. Recent studies indicated that Modafinil prevents inflammation in animal models of neurodegeneration. However, the effect of Modafinil on the behavioral changes induced by systemic inflammation is still unknown. Thus, the aim of the present study was to evaluate the effect of Modafinil pretreatment in the Lipopolysaccharide (LPS)-induced sickness behavior, and determine the role of dopaminergic D1 receptor in this phenomenon. Adult male C57BL/6J mice were pretreated with Vehicle or Modafinil and, 30 min later, received a single saline or LPS administration, followed by open field and elevated plus maze test 2 h later. Modafinil treatment prevented the LPS-induced increases in immobility and anxiety-like behavior. The pharmacological blockage of the dopaminergic D1R by the drug SCH-23390 counteracted the preventive effect of Modafinil on locomotion and anxiety-like behavior. Our results indicate that Modafinil pretreatment prevented the behavioral inhibition of an acute LPS challenge. The dopaminergic D1 receptor signaling is essential to the Modafinil effects on locomotion and anxiety. This evidence suggests that Modafinil treatment may be useful to prevent inflammation-related behavioral inhibition, possibly due to a neuroimmune mechanism.

Neuroinflammatory and central nervous system (CNS) demyelinating diseases have most of its pathological features based on immune cells infiltrating brain parenchyma and leading to neuronal death and focal or diffuse destruction of the CNS architecture, as extensively reviewed (Rodriguez 2007; Weiner 2008; Shie FS 2011). In this context, the role for resident and infiltrating inflammatory cells is very relevant, as they may be both the trigger and the maintainers of the neuroinflammatory process (Almolda B 2011). The combination of interesting concepts of neurology to the immunology laboratory, has rendered glial cells with a more dynamic and immunological shape.

OBJECTIVES: FTY720 modulates CD4+T cells by the augmentation of regulatory T cell activity, secretion of suppressive cytokines and suppression of IL-17 secretion by Th17 cells. To further understand the process of graft rejection/acceptance, we evaluated skin allograft survival and associated events after FTY720 treatment. METHODS: F1 mice (C57BL/6xBALB/c) and C57BL/6 mice were used as donors for and recipients of skin transplantation, respectively. The recipients were transplanted and either not treated or treated with FTY720 by gavage for 21 days to evaluate the allograft survival. In another set of experiments, the immunological evaluation was performed five days post-transplantation. The spleens, axillary lymph nodes and skin allografts of the recipient mice were harvested for phenotyping (flow cytometry), gene expression (real-time PCR) and cytokine (Bio-Plex) analysis. RESULTS: The FTY720 treatment significantly increased skin allograft survival, reduced the number of cells in the lymph nodes and decreased the percentage of Tregs at this site in the C57BL/6 recipients. Moreover, the treatment reduced the number of graft-infiltrating cells and the percentage of CD4+ graft-infiltrating cells. The cytokine analysis (splenocytes) showed decreased levels of IL-10, IL-6 and IL-17 in the FTY720-treated mice. We also observed a decrease in the IL-10, IL-6 and IL-23 mRNA levels, as well as an increase in the IL-27 mRNA levels, in the splenocytes of the treated group. The FTY720-treated mice exhibited increased mRNA levels of IL-10, IL-27 and IL-23 in the skin graft. CONCLUSIONS: Our results demonstrated prolonged but not indefinite skin allograft survival by FTY720 treatment. This finding indicates that the drug did not prevent the imbalance between Tr1 and Th17 cells in the graft that led to rejection.

Experimental autoimmune uveitis (EAU) is a well established model for immune-mediated organ-specific disease. Our group has recently shown that theM. lepraeHsp65 aggravated the uveitis in mice; in the present study, we evaluated the action ofM. leprae K409Amutant protein and the synthetic peptides Leader pep andK409Apep (covering amino acids residues 352–371 of WT andK409Aproteins ofM. lepraeHsp65, resp.) on the pathogenesis of EAU. Mice received the 161–180 IRBP peptide andB. pertussistoxin followed by the intraperitoneal inoculation ofK409Aprotein or the Leader pep orK409Apep. The Leader pep aggravated the disease, but mice receiving theK409Apep did not develop the disease and presented an increase in IL-10 levels by spleen cells and a decrease in the percentage of CD4+ IFN-γ+ T cells. Moreover, animals receiving the Leader pep presented the highest scores of the disease associated with increase percentage of CD4+ IFN-γ+ T cells. These results would contribute to understanding of the pathogenesis of EAU and support the concept that immune responses to Hsp are of potential importance in exacerbating, perpetuating, or even controlling organ-restricted autoimmune diseases, and it is discussed the irreversibility of autoimmune syndromes.

Mesenchymal stromal cells (MSCs) are undifferentiated multipotent cells endowed with the capacity for self-renewal and the potential to differentiate into several distinct cell lineages [1]. It is well established that adult MSCs constitute a reservoir found within connective tissues of most organs, and whose biological function is involved in the maintenance and repair of tissues throughout the postnatal life of an individual. Over the past years we and others have shown that menstrual blood, the endometrium and fallopian tubes are very rich sources of MSCs and able to differentiate into different cell lineages in vitro and/or in vivo [2, 3]. The unique regenerative capacity of the human endometrium following menstruation, postpartum, surgical procedures (uterine curettage, endometrial ablation) and in postmenopausal women undergoing hormonal replacement therapy suggests that MSCs niches present in this tissue are responsible, at least in part, for this process. This makes these cells a very interesting approach to studies in regenerative medicine, especially in autoimmune disorders. Multiple sclerosis (MS) is a debilitating and neurodegenerative autoimmune disease with a significant social burden. It is mainly characterized by central nervous system (CNS) inflammation, gliosis, neuronal death and demyelination [4, 5]. Its murine model, experimental autoimmune encephalomyelitis (EAE), has generated many important data concerning MS pathology and treatment [6–9]. In EAE, mice are subcutaneously immunized with myelin-derived antigens such as myelin oligodendrocyte glycoprotein (MOG35-55), myelin basic protein (MBP) and also proteolipoprotein (PLP) [6]. In the periphery T CD4 cells differentiate into Th1 and Th17 cells and have been implicated in the pathogenesis of EAE [10–12]. Although IFN-γ and ILStem Cell Rev and Rep (2012) 8:940–952 DOI 10.1007/s12015-011-9338-3

The wake-promoting drug Modafinil has been used for many years for treatment of Narcolepsy and Excessive Daytime Sleepiness, due to a dopamine-related psychostimulant action. Recent studies have indicated that Modafinil prevents neuroinflammation in some animal models. Thus, the aim of the present study was to evaluate the effect of Modafinil pretreatment in the Lipopolysaccharide (LPS)-induced depressive-like behavior. Adult male C57BL/6J mice were pretreated with Vehicle or Modafinil (Stavigile, Libbs; 90 mg/kg, i.p.) and, 30 minutes later, received a single saline or LPS administration (E.coli serotype 0127:B8; 2 mg/kg, i.p.), and were submitted to a 2% sucrose preference test during the next 24 hours. After this period, mice were subjected to tail suspension test, followed by flow cytometry with whole brain for CD11b+CD45+ cells. Modafinil treatment prevented the LPS-induced impairment in sucrose preference (anhedonia), as well as prevented the increased immobility in tail suspension test induced by LPS (learned helplessness). In addition, LPS challenge markedly increased the number of CNS-infiltrating macrophages (CD11b+CD45High), but not microglia (CD11b+CD45low), an effect that was prevented by Modafinil pretreatment (p 0.05). Our results indicate that Modafinill pretreatment was able to prevent the depressive-like effects of an acute LPS injection, a finding that is possibly linked with the CNS-infiltrating macrophages. This evidence suggests that Modafinil treatment might be useful to prevent inflammation-related depression, possibly due to a neuroimmune mechanism.

Cigarette smoke-induced chronic obstructive pulmonary disease is a very debilitating disease, with a very high prevalence worldwide, which results in a expressive economic and social burden. Therefore, new therapeutic approaches to treat these patients are of unquestionable relevance. The use of mesenchymal stromal cells (MSCs) is an innovative and yet accessible approach for pulmonary acute and chronic diseases, mainly due to its important immunoregulatory, anti-fibrogenic, anti-apoptotic and pro-angiogenic. Besides, the use of adjuvant therapies, whose aim is to boost or synergize with their function should be tested. Low level laser (LLL) therapy is a relatively new and promising approach, with very low cost, no invasiveness and no side effects. Here, we aimed to study the effectiveness of human tube derived MSCs (htMSCs) cell therapy associated with a 30mW/3J—660 nm LLL irradiation in experimental cigarette smoke-induced chronic obstructive pulmonary disease. Thus, C57BL/6 mice were exposed to cigarette smoke for 75 days (twice a day) and all experiments were performed on day 76. Experimental groups receive htMSCS either intraperitoneally or intranasally and/or LLL irradiation either alone or in association. We show that co-therapy greatly reduces lung inflammation, lowering the cellular infiltrate and pro-inflammatory cytokine secretion (IL-1β, IL-6, TNF-α and KC), which were followed by decreased mucus production, collagen accumulation and tissue damage. These findings seemed to be secondary to the reduction of both NF-κB and NF-AT activation in lung tissues with a concomitant increase in IL-10. In summary, our data suggests that the concomitant use of MSCs + LLLT may be a promising therapeutic approach for lung inflammatory diseases as COPD.

Introduction: T cells play a crucial role in adaptive immune responses and neuroinflammatory diseases such as multiple sclerosis. Glutamate is one of the most abundant neurotransmitter in the central nervous system; it can acts through two different receptor families: metabotropic and ionotropic. It has been demonstrated that T cells can be the target of glutamate during antigen presentation and immunological synapses, however, little is known about its role on T cell survival. Methods and Results: To evaluate whether NMDAr ligands exert a role in T cell survival, we harvested spleen cells from C57BL/6 female mice and cultivated in the presence of anti-CD3 (1µg/mL) in vitro for 5 days. On day 5, cells were stained for CD4+/CD8+ and 7-AAD and data were acquired by flow cytometric analysis. NMDAr blockage by MK801 induced cell death while NMDA agonist did not affect T proliferation and T cell numbers. Conclusion: Our data demonstrate that NMDAr exert a crucial role in T cell survival. These findings not only contribute to the advantage of the neuroimmunology field but also suggest that T cells which infiltrate the central nervous system could be target of the neurotransmitter glutamate via NMDAr in neuroinflammatory diseases.