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BackgroundEmerging evidence of antibody-independent functions, as well as the clinical efficacy of anti-CD20 depleting therapies, helped to reassess the contribution of B cells during multiple sclerosis (MS) pathogenesis.ObjectiveTo investigate whether CD19+ B cells may share expression of the serine-protease granzyme-B (GzmB), resembling classical cytotoxic CD8+ T lymphocytes, in the peripheral blood from relapsing-remitting MS (RRMS) patients.MethodsIn this study, 104 RRMS patients during different treatments and 58 healthy donors were included. CD8, CD19, Runx3, and GzmB expression was assessed by flow cytometry analyses.ResultsRRMS patients during fingolimod (FTY) and natalizumab (NTZ) treatment showed increased percentage of circulating CD8+GzmB+ T lymphocytes when compared to healthy volunteers. An increase in circulating CD19+GzmB+ B cells was observed in RRMS patients during FTY and NTZ therapies when compared to glatiramer (GA), untreated RRMS patients, and healthy donors but not when compared to interferon-β (IFN). Moreover, regarding Runx3, the transcriptional factor classically associated with cytotoxicity in CD8+ T lymphocytes, the expression of GzmB was significantly higher in CD19+Runx3+-expressing B cells when compared to CD19+Runx3- counterparts in RRMS patients.ConclusionsCD19+ B cells may exhibit cytotoxic behavior resembling CD8+ T lymphocytes in MS patients during different treatments. In the future, monitoring “cytotoxic” subsets might become an accessible marker for investigating MS pathophysiology and even for the development of new therapeutic interventions.

A major aim in MS field has been the search for biomarkers that enable accurate detection of neuronal damage. Besides MRI, recent studies have shown that neuroaxonal damage can also be tracked by neurofilament detection. Nevertheless, before widespread implementation, a better understanding of the principal contributors for this biomarker is of paramount importance. Therefore, we analyzed neurofilament light chain (NfL) in relapsing (RMS) and progressive MS (PMS), addressing which MRI and clinical variables are better related to this biomarker.Forty-seven MS patients underwent MRI (3T) and cerebrospinal fluid (CSF) sampling. We measured NfL concentrations using ELISA (UmanDiagnostics) and performed multivariable regression analysis to assess the contribution of clinical and MRI metrics to NfL.NfL correlated with previous clinical activity in RMS (p 0.001). In RMS, NfL also correlated with Gad+ and cortical lesion volumes. However, after multivariable analysis, only cortical lesions and relapses in previous 12 months remained in the final model (RCSF NfL levels are increased in RMS and associated with relapses and cortical lesions. Although NfL levels were correlated with Gad+ lesion volume, this association did not persist in multivariable analysis after controlling for previous clinical activity. We encourage controlling for previous clinical activity when testing the association of NfL with MRI. In PMS, the major contributor to NfL was T1-hypointense lesion volume.

Recently, it was shown that highly effective anti-CD20 therapies used for MS patients not only deplete CD20+ B cells, but also a small subset of T cells expressing CD20 surface marker (CD3+CD20+ T cells). Here we demonstrated that, in progressive MS patients, CD3+CD20+ T cells share the ability to express cytotoxic factors such as perforin and serine-protease granzyme-B (GzmB), classically associated with CD8+ T cells functionality. Beyond it, cluster analyses show that a set of activation markers and transcriptional factors related with CD8 effector program are also expressed in CD3+CD20+ T cells. Further characterization of surface and functional markers from CD3+CD20+ T subsets may be helpful for development of new therapeutic strategies mainly for progressive MS patients, as well as for assessing pathophysiological effects of highly effective anti-CD20 therapies.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as coronavirus disease-2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality1,2. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here we show that SARS-CoV-2 infects human CD4+T helper cells, but not CD8+T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.

Made available in DSpace on 2020-12-12T02:25:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Fundo de Apoio ao Ensino, à Pesquisa e Extensão, Universidade Estadual de Campinas Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) COVID-19 can result in severe lung injury. It remained to be determined why diabetic individuals with uncontrolled glucose levels are more prone to develop the severe form of COVID-19. The molecular mechanism underlying SARS-CoV-2 infection and what determines the onset of the cytokine storm found in severe COVID-19 patients are unknown. Monocytes and macrophages are the most enriched immune cell types in the lungs of COVID-19 patients and appear to have a central role in the pathogenicity of the disease. These cells adapt their metabolism upon infection and become highly glycolytic, which facilitates SARS-CoV-2 replication. The infection triggers mitochondrial ROS production, which induces stabilization of hypoxia-inducible factor-1α (HIF-1α) and consequently promotes glycolysis. HIF-1α-induced changes in monocyte metabolism by SARS-CoV-2 infection directly inhibit T cell response and reduce epithelial cell survival. Targeting HIF-1ɑ may have great therapeutic potential for the development of novel drugs to treat COVID-19. Diabetic people with uncontrolled blood glucose levels have a greater risk to develop severe COVID-19 disease. Codo et al. show that elevated glucose levels and glycolysis promote SARS-CoV-2 (CoV-2) replication and cytokine production in monocytes through a mitochondrial ROS/hypoxia-inducible factor-1α dependent pathway, resulting in T cell dysfunction and epithelial cell death. Laboratory of Immunometabolism Department of Genetics Evolution Microbiology and Immunology Institute of Biology University of Campinas Department of Genetics Evolution Microbiology and Immunology Institute of Biology University of Campinas Department of Biochemistry and Tissue Biology Institute of Biology University of Campinas Department of Genetics at Ribeirao Preto Medical School University of Sao Paulo, Ribeirao Preto Department of Clinical and Toxicological analyses School of Pharmaceutical Sciences University of São Paulo Brazilian Biosciences National Laboratory (LNBio), Campinas Department of Animal Biology Institute of Biology University of Campinas, Campinas Department of Internal Medicine School of Medical Sciences University of Campinas, Campinas Department of Clinical Medicine School of Medical Sciences University of Campinas, Campinas Hematology and Hemotherapy Center University of Campinas, Campinas Obesity and Comorbidities Research Center (OCRC) University of Campinas Experimental Medicine Research Cluster (EMRC) University of Campinas Department of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP), Botucatu D'Or Institute for Research and Education (IDOR) Instituto Nacional de Biomarcadores em Neuropsiquiatria Conselho Nacional de Desenvolvimento Científico e Tecnológico Department of Structural and Functional Biology Institute of Biosciences São Paulo State University (UNESP), Botucatu FAPESP: 20/04579-7 FAPESP: 2015/15626-8 FAPESP: 2016/18031-8 FAPESP: 2016/23328-0 FAPESP: 2017/01184-9 FAPESP: 2018/22505-0 FAPESP: 2019/00098-7 FAPESP: 2019/06372-3 FAPESP: 2020/04522-5 FAPESP: 2020/04558-0 FAPESP: 2020/04583-4 FAPESP: 2020/04746-0 FAPESP: 2020/04919-2 Fundo de Apoio ao Ensino, à Pesquisa e Extensão, Universidade Estadual de Campinas: 2274/20

Pathogenic CD4+ T cells are capable of initiating neuroinflammation in experimental autoimmune encephalomyelitis (EAE). However, the precise effector mechanism of these autoaggressive CD4+ T cells is not entirely elucidated. Here, we demonstrated that pathogenic CD4+ T cells, upon autoantigen stimulation, developed a cytotoxic phenotype at the onset of EAE. The cytotoxic activity of pathogenic CD4+ T cells was sufficient to explain the initial myelin lesion. Consistently, CD4+ T cells of peripheral blood (PBMCs) and cerebrospinal fluid (CSF) from relapse-remitting multiple sclerosis (RRMS) patients present an enhancement of the cytotoxic profile in comparison with healthy control (HC). Moreover, cytotoxic CD4+ T cells (CD4-CTLs) are restrained in the PBMCs of Natalizumab-treated RRMS patients. Mechanistically, autoaggressive CD4-CTLs matched the majority of the molecular pathways of effector CD8+ T cells. Altogether, our findings point to potential new targets for monitoring MS diagnosis, treatment, and the development of novel therapeutic avenues.

There is increasing evidence suggesting that one of the most relevant pathophysiological features of Alzheimer's disease (AD) is neuroinflammation, which plays an important role in the production and regulation of AD-related proteins (amyloid beta (Aβ) and Tau) and exacerbates AD pathology. Neuroinflammation can also be induced by systemic influences (factors from outside the central nervous system). However, the role of systemic inflammation in AD pathophysiology is much less understood. Thus, our main objective in this study was to verify whether the presence of serum cytokines (IL-1β, IL-6, IL-10, IL-12, and TNF-α) affects different AD biomarkers: Aβ1-42 and Tau protein levels, hippocampal volumes (HV), and default mode network functional connectivity (DMN FC) in healthy elderly controls, amnestic mild cognitive impairment (aMCI) patients due to AD, and mild AD patients. To accomplish this, we acquired 3-T MRI, blood, and cerebrospinal fluid (CSF) samples from 42 healthy controls, 55 aMCI patients due to AD, and 33 mild AD patients. Comparing the groups, we found that the mild AD patients presented smaller HV, disrupted DMN FC, and proportionally less IL-1β than the controls. The aMCI patients only differed from the controls in DMN FC. In intra-group comparison, aMCI and mild AD with detectable levels of cytokines (TNF-α, IL-1β, IL-10, and IL-12) had decreased DMN FC. On the other hand, patients with detectable levels of IL-10 and IL-12 presented a more favorable AD biomarkers profile (larger HV, more CSF Aβ1-42, and less p-Tau), indicating a possible protective role of these ILs. Our findings indicate a possible relationship between systemic inflammation with DMN FC disruption, hippocampal atrophy, and CSF protein levels in the subjects with mild AD and aMCI.

COVID-19 can result in severe lung injury. It remained to be determined why diabetic individuals with uncontrolled glucose levels are more prone to develop the severe form of COVID-19. The molecular mechanism underlying SARS-CoV-2 infection and what determines the onset of the cytokine storm found in severe COVID-19 patients are unknown. Monocytes/macrophages are the most enriched immune cell types in the lungs of COVID-19 patients and appear to have a central role in the pathogenicity of the disease. These cells adapt their metabolism upon infection and become highly glycolytic, which facilitates SARS-CoV-2 replication. The infection triggers mitochondrial ROS production, which induces stabilization of hypoxia-inducible factor- 1α (HIF - 1α) and consequently promotes glycolysis. HIF- 1α-induced changes in monocyte metabolism by SARS-CoV-2 infection directly inhibit T cell response and reduce epithelial cell survival. Targeting HIF-1 ɑ may have great therapeutic potential for the development of novel drugs to treat COVID-19.

Our group is interested in the cytotoxic mechanism during autoimmune neuroinflammation. Unexpectedly, we come across a case that presents a massive enhancement of cytotoxic behavior in lymphocytes, either in peripheral blood and cerebrospinal fluid. Interestingly, this specific patient was refractory to Methylprednisolone treatment. Hypothetically, the cytotoxic activity could represent a novel and complementary effector mechanism to NMOSD pathogenesis. Nevertheless, further investigation is needed to evaluate the extension and the clinical relevance of our finds.

Evidence indicates that reprogramming of metabolism is critically important for the differentiation of CD4 + T lymphocytes, and the manipulation of metabolic pathways in these cells may shape their fate and function. Distinct subgroups from T lymphocytes, such as Th17, adopt specific metabolic programmes to support their needs. Some important metabolic reactions, such as glycolysis, oxidative phosphorylation, are considered important for the differentiation of these lymphocytes. Since their discovery nearly a decade ago, Th17 lymphocytes have received significant attention because of their role in the pathology of several immune-mediated inflammatory diseases such as multiple sclerosis. In this review, it will be discussed as the involvement of T cell metabolism and as metabolic reprogramming in activated T cells dictates fate decisions to Th17. The involvement of nuclear receptors such as RORyt e PPARs in the induction of Th17 cells was also discussed. Understanding the metabolic pathways involved in the differentiation of the distinct subgroups of T lymphocytes helps in the design of promising therapeutic proposals.

Photodynamic therapy is a minimally invasive health technology used to treat cancer and other non-malignant diseases, as well as inactivation of viruses, bacteria and fungi. In this work, we sought to combine the phototherapy technique using low intensity LED (660 nm) to induce ablation in melanoma tumor in mice treated with nanoparticles. In vitro and in vivo studies were conducted, and our results demonstrated that multi-walled carbon nanotubes (MWCNTs) do not destroy tumor cells in vivo, but stimulate the inflammatory process and angiogenesis. Reduced graphene oxide (rGO), has been shown to play a protective role associated with the LED ablation, inducing necrosis, stimulation of immune response by lymphoproliferation, and decreased tumor mass in vivo. We consider that LED alone can be very effective in controlling the growth of melanoma tumors and its association with rGO is potentiated.

Given the low detection rates of CSF IgG-Oligoclonal bands (IgG-OCB) in non-European Multiple Sclerosis (MS) patients and higher specificity of the MRZH-reaction, we evaluated whether associating MRZH-reaction to CSF IgG-OCB detection improved investigation of suspected MS. Paired CSF and sera were analyzed for IgG-OCB and polyspecific viral antibodies. IgG-OCB were detected in 72% of MS patients and an MRZH-reaction in 67%. Combining IgG-OCB and MRZH raised detection of IgG abnormalities to 97% of studied MS patients. Detection of IgG-OCB and/or ≥2 MRZH antibodies showed sensitivity of 88% and specificity of 92% for MS, versus 72% and 96% for IgG-OCB alone.