RESUMO
Whilst the contribution of peripheral and central inflammation to neurodegeneration in Parkinson's disease and the role of the immune response in this disorder are well known, the effects of the anti-inflammatory response on the disease have not been described in depth. This study is aimed to assess the changes in the regulatory/inflammatory immune response in recently diagnosed, untreated PD patients and a year after. Twenty-one PD patients and 19 healthy controls were included and followed-up for 1 year. The levels of immunoregulatory cells (CD4+ Tregs, Bregs, and CD8+ Tregs); classical, nonclassical, and intermediate monocytes, and proinflammatory cells (Th1, Th2, and Th17) were measured by flow cytometry. Cytokine levels were determined by ELISA. Clinical follow-up was based on the Hoehn & Yahr and UDPRS scales. Our results indicate that the regulatory response in PD patients on follow-up was characterized by increased levels of active Tregs, functional Tregs, TR1, IL-10-producing functional Bregs, and IL-10-producing classical monocytes, along with decreased counts of Bregs and plasma cells. With respect to the proinflammatory immune response, peripheral levels of Th1 IFN-γ+ cells were decreased in treated PD patients, whilst the levels of CD4+ TBET+ cells, HLA-DR+ intermediate monocytes, IL-6, and IL-4 were increased after a 1-year follow-up. Our main finding was an increased regulatory T cell response after a 1-year follow-up and its link with clinical improvement in PD patients. In conclusion, after a 1-year follow-up, PD patients exhibited increased levels of regulatory populations, which correlated with clinical improvement. However, a persistent inflammatory environment and active immune response were observed.
Assuntos
Linfócitos B Reguladores , Interleucina-10 , Doença de Parkinson , Linfócitos T Reguladores , Humanos , Doença de Parkinson/imunologia , Doença de Parkinson/sangue , Masculino , Feminino , Linfócitos T Reguladores/imunologia , Interleucina-10/imunologia , Interleucina-10/sangue , Linfócitos B Reguladores/imunologia , Pessoa de Meia-Idade , Idoso , SeguimentosRESUMO
APRIL (A Proliferation-Inducing Ligand), a member of the TNF superfamily, was initially described for its ability to promote proliferation of tumor cells in vitro. Moreover, this cytokine has been related to the pathogenesis of different chronic inflammatory diseases, such as rheumatoid arthritis. This study aimed to evaluate the ability of APRIL in regulating B cell-mediated immune response in the antigen-induced arthritis (AIA) model in mice. AIA was induced in previously immunized APRIL-transgenic (Tg) mice and their littermates by administration of antigen (mBSA) into the knee joints. Different inflammatory cell populations in spleen and draining lymph nodes were analyzed using flow cytometry and the assay was performed in the acute and chronic phases of the disease, while cytokine levels were assessed by ELISA. In the acute AIA, APRIL-Tg mice developed a less severe condition and a smaller inflammatory infiltrate in articular tissues when compared with their littermates. We also observed that the total cellularity of draining lymph nodes was decreased in APRIL-Tg mice. Flow cytometry analysis revealed an increase of CD19+IgM+CD5+ cell population in draining lymph nodes and an increase of CD19+CD21hiCD23hi (B regulatory) cells in APRIL-Tg mice with arthritis as well as an increase of IL-10 and CXCL13 production in vitro.
Assuntos
Artrite Experimental , Linfócitos B Reguladores , Camundongos Transgênicos , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Animais , Camundongos , Artrite Experimental/imunologia , Artrite Experimental/patologia , Linfócitos B Reguladores/imunologia , Interleucina-10/metabolismo , Linfonodos/imunologia , Linfonodos/patologia , Baço/imunologia , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genéticaRESUMO
Multiple sclerosis (MS) is currently thought to arise by interactions between genetic susceptibility and environmental factors. Infections in general trigger autoimmune responses causing clinical manifestations of disease. However, as a result of regulatory T (Treg)- and regulatory B (Breg)-cell induction, helminth infections tend to dampen disease activity. IL-35, the newest member of the IL-12 family, is an inhibitory cytokine composed of an EBI3ß chain subunit, and an IL-12p35 subunit. The aim of this study was to investigate the role of IL-35 during parasite infections occurring in individuals with MS. Numbers of IL-35-producing Breg cells are higher in CSF from helminth-infected than from uninfected MS subjects, a finding associated with decreased MRI disease activity. Interestingly, stimulation of CD19+ B cells with IL-35 promotes conversion of these cells to Breg cells producing both IL-35 and IL-10. Coculture of B cells from helminth-infected MS patients inhibits proliferation of Th1 and Th17 myelin peptide-specific T cells, as well as production of IFN-γ and IL-17. Following activation, CD4+ CD25+ Treg cells significantly upregulate expression of EBI3 and IL-12p35 mRNA. Furthermore, CD4+ CD25- T cells activated in the presence of IL-35 induce a population of cells with regulatory function, known as iTR35. Finally, B cells from normal individuals cultured in vitro in the presence of the helminth antigen SEA increase expression of the transcription BATF, IRF4 and IRF8, acquiring a pattern similar to that of IL-35 Breg cells. These data highlight the important immunoregulatory effects of IL-35 on both Breg and Treg cells, observed in helminth-infected MS subjects.
Assuntos
Linfócitos B Reguladores/imunologia , Helmintíase/imunologia , Interleucinas/metabolismo , Esclerose Múltipla/complicações , Linfócitos T Reguladores/imunologia , Adulto , Animais , Linfócitos B Reguladores/metabolismo , Feminino , Helmintíase/parasitologia , Helmintos/imunologia , Helmintos/isolamento & purificação , Interações Hospedeiro-Parasita , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Linfócitos T Reguladores/metabolismo , Células Th1/imunologia , Células Th17/imunologiaRESUMO
Regulatory B cells (Bregs) is a term that encompasses all B cells that act to suppress immune responses. Bregs contribute to the maintenance of tolerance, limiting ongoing immune responses and reestablishing immune homeostasis. The important role of Bregs in restraining the pathology associated with exacerbated inflammatory responses in autoimmunity and graft rejection has been consistently demonstrated, while more recent studies have suggested a role for this population in other immune-related conditions, such as infections, allergy, cancer, and chronic metabolic diseases. Initial studies identified IL-10 as the hallmark of Breg function; nevertheless, the past decade has seen the discovery of other molecules utilized by human and murine B cells to regulate immune responses. This new arsenal includes other anti-inflammatory cytokines such IL-35 and TGF-ß, as well as cell surface proteins like CD1d and PD-L1. In this review, we examine the main suppressive mechanisms employed by these novel Breg populations. We also discuss recent evidence that helps to unravel previously unknown aspects of the phenotype, development, activation, and function of IL-10-producing Bregs, incorporating an overview on those questions that remain obscure.
Assuntos
Linfócitos B Reguladores/imunologia , Linfócitos B Reguladores/metabolismo , Imunomodulação , Animais , Subpopulações de Linfócitos B/metabolismo , Linfócitos B Reguladores/citologia , Biomarcadores , Diferenciação Celular , Citocinas/genética , Citocinas/metabolismo , Regulação da Expressão Gênica , Humanos , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismoRESUMO
Despite the growing importance of the regulatory function of B cells in many infectious diseases, their immunosuppressive role remains elusive in chronic Chagas disease (CCD). Here, we studied the proportion of different B cell subsets and their capacity to secrete IL-10 ex vivo in peripheral blood from patients with or without CCD cardiomyopathy. First, we immunophenotyped peripheral blood mononuclear cells from patients according to the expression of markers CD19, CD24, CD38 and CD27 and we showed an expansion of total B cell and transitional CD24highCD38high B cell subsets in CCD patients with cardiac involvement compared to non-infected donors. Although no differences were observed in the frequency of total IL-10 producing B cells (B10) among the groups, CCD patients with cardiac involvement showed an increased proportion of naïve B10 cells and a tendency to a higher frequency of transitional B10 cells compared to non-infected donors. Our research demonstrates that transitional B cells are greatly expanded in patients with the cardiac form of CCD and these cells retain the ability to secrete IL-10. These findings provide insight into the phenotypic distribution of regulatory B cells in CCD, an important step towards new strategies to prevent cardiomyopathy associated with T. cruzi infection.
Assuntos
Antígenos CD/imunologia , Linfócitos B Reguladores/imunologia , Doença de Chagas/imunologia , Interleucina-10/imunologia , Adulto , Linfócitos B Reguladores/patologia , Doença de Chagas/patologia , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by progressive joint destruction associated with increased pro-inflammatory mediators. In inflammatory microenvironments, exogenous ATP (eATP) is hydrolyzed to adenosine, which exerts immunosuppressive effects, by the consecutive action of the ectonucleotidases CD39 and CD73. Mature B cells constitutively express both ectonucleotidases, converting these cells to potential suppressors. Here, we assessed CD39 and CD73 expression on B cells from treated or untreated patients with RA. Neither the frequency of CD73+CD39+ and CD73-CD39+ B cell subsets nor the levels of CD73 and CD39 expression on B cells from untreated or treated RA patients showed significant changes in comparison to healthy controls (HC). CpG+IL-2-stimulated B cells from HC or untreated RA patients increased their CD39 expression, and suppressed CD4+ and CD8+ T cell proliferation and intracellular TNF-production. A CD39 inhibitor significantly restored proliferation and TNF-producing capacity in CD4+ T cells, but not in CD8+ T cells, from HC and untreated RA patients, indicating that B cells from untreated RA patients conserved CD39-mediated regulatory function. Good responder patients to therapy (R-RA) exhibited an increased CD39 but not CD73 expression on B cells after treatment, while most of the non-responder (NR) patients showed a reduction in ectoenzyme expression. The positive changes of CD39 expression on B cells exhibited a negative correlation with disease activity and rheumatoid factor levels. Our results suggest modulating the ectoenzymes/ADO pathway as a potential therapy target for improving the course of RA.
Assuntos
Apirase/metabolismo , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Linfócitos B/imunologia , Linfócitos B/metabolismo , Imunomodulação , Adenosina/metabolismo , Apirase/genética , Artrite Reumatoide/patologia , Artrite Reumatoide/terapia , Linfócitos B Reguladores/imunologia , Linfócitos B Reguladores/metabolismo , Estudos de Casos e Controles , Citocinas/biossíntese , Gerenciamento Clínico , Suscetibilidade a Doenças , Expressão Gênica , Humanos , Ativação Linfocitária , Contagem de Linfócitos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Resultado do TratamentoRESUMO
INTRODUCTION: Tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM) is a disease caused by human T-cell lymphotropic virus type 1 (HTLV-I) that mainly infects CD4 T cells-for example, those of the CD4+CD25hiFOXP3+ [Treg] phenotype-where it inhibits forkhead box protein P3 (FOXP3) expression and promotes interferon-γ (IFN-γ) expression. However, the role it exerts on regulatory B cells (CD19+CD24hiCD38hi; Breg) is unknown. METHODS: The frequencies of Treg and Breg cells was evaluated and the Th1 profiles were assessed in TSP/HAM patients and healthy control subjects. RESULTS: Low percentages of Breg cells and high production of IFN-γ were observed in patients compared to those in healthy control subjects. CONCLUSIONS: The low percentage of Breg cells in patients and the increase in the frequency of Th1 cells suggest an imbalance in the control of the inflammatory response that contributes to the immunopathogenesis of TSP/HAM.
Assuntos
Linfócitos B Reguladores/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Interferon gama/imunologia , Paraparesia Espástica Tropical/imunologia , Linfócitos T Reguladores/imunologia , Adolescente , Linfócitos B Reguladores/virologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Feminino , Humanos , Masculino , Paraparesia Espástica Tropical/virologia , Linfócitos T Reguladores/virologia , Carga ViralRESUMO
Since its discovery, over 30 years ago, CD5 has been used as a marker to identify T cells, B1-a cells, and B cell chronic lymphocytic leukemia cells. Throughout the years, many studies have described the functional relevance of CD5 as a modulator of T and B cell receptor signaling. However, it has not been until recent years that CD5 has emerged as a functional receptor in other areas of the immune system. Here, we review some of the most important aspects of CD5 as a modulator of TCR and BCR signaling, cell survival receptor both in T and B cells during health and disease, as well as the newly discovered roles of this receptor in thymocyte selection, T cell effector differentiation, and immune tolerance. CD5 was found to promote T cell survival by protecting autoreactive T cell from activation-induced cell death, to promote de novo induction of regulatory T cells in the periphery, to modulate Th17 and Th2 differentiation, and to modulate immune responses by modulating dendritic cell functions. CD5 is overexpressed in Tregs and Bregs, which are fundamental to maintain immune homeostasis. The newly established roles of CD5 in modulating different aspects of immune responses identify this receptor as an immune checkpoint modulator, and therefore it could be used as a target for immune intervention in different pathologies such as cancer, autoimmune diseases or infections.
Assuntos
Doenças Autoimunes/genética , Linfócitos B Reguladores/imunologia , Antígenos CD5/genética , Doenças Transmissíveis/genética , Neoplasias/genética , Linfócitos T Reguladores/imunologia , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Linfócitos B Reguladores/patologia , Antígenos CD5/imunologia , Diferenciação Celular , Sobrevivência Celular , Doenças Transmissíveis/imunologia , Doenças Transmissíveis/patologia , Células Dendríticas/imunologia , Células Dendríticas/patologia , Regulação da Expressão Gênica , Homeostase/genética , Homeostase/imunologia , Humanos , Tolerância Imunológica , Ativação Linfocitária , Neoplasias/imunologia , Neoplasias/patologia , Receptores de Antígenos de Linfócitos B/genética , Receptores de Antígenos de Linfócitos B/imunologia , Receptores de Antígenos de Linfócitos T/genética , Receptores de Antígenos de Linfócitos T/imunologia , Transdução de Sinais , Linfócitos T Reguladores/patologia , Células Th17/imunologia , Células Th17/patologiaRESUMO
Abstract INTRODUCTION: Tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM) is a disease caused by human T-cell lymphotropic virus type 1 (HTLV-I) that mainly infects CD4 T cells-for example, those of the CD4+CD25hiFOXP3+ [Treg] phenotype-where it inhibits forkhead box protein P3 (FOXP3) expression and promotes interferon-γ (IFN-γ) expression. However, the role it exerts on regulatory B cells (CD19+CD24hiCD38hi; Breg) is unknown. METHODS: The frequencies of Treg and Breg cells was evaluated and the Th1 profiles were assessed in TSP/HAM patients and healthy control subjects. RESULTS: Low percentages of Breg cells and high production of IFN-γ were observed in patients compared to those in healthy control subjects. CONCLUSIONS: The low percentage of Breg cells in patients and the increase in the frequency of Th1 cells suggest an imbalance in the control of the inflammatory response that contributes to the immunopathogenesis of TSP/HAM.
Assuntos
Humanos , Masculino , Feminino , Adolescente , Linfócitos T CD4-Positivos/imunologia , Paraparesia Espástica Tropical/imunologia , Interferon gama/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos B Reguladores/imunologia , Linfócitos T CD4-Positivos/virologia , Paraparesia Espástica Tropical/virologia , Linfócitos T Reguladores/virologia , Linfócitos T CD8-Positivos/virologia , Carga Viral , Linfócitos B Reguladores/virologiaRESUMO
Background: B cells play an important role in the development and maintenance of rheumatoid arthritis (RA). Although IL-10-producing B cells represent a major subset of regulatory B cells (Bregs) able to suppress autoimmune and inflammatory responses, recent reports showed that B cell-mediated immune suppression may also occur independent of IL-10. For instance, B cells can modulate T cell immune responses through the expression of regulatory molecules such as PD-L1. So far, PD-L1-expressing B cells have not been analyzed in RA patients. Objective: To analyze the frequency of PD-L1-expressing B cells in the peripheral blood of RA patients compared to healthy controls (HC) matched for sex and age, their function on T cell response and their changes in response to therapy. Methods: Fresh peripheral blood B cells from RA patients and HC were characterized by flow cytometry and their functionality assessed in a co-culture system with autologous T cells. Results: The frequencies of CD19+PD-L1+ B cells, CD24hiCD38-PD-L1+ and CD24hiCD38hiPD-L1+ B cells were significantly lower in untreated RA patients than in HC. In a follow-up study, the frequencies of PD-L1+ B cells (CD19+PD-L1+ B cells, CD24hiCD38-PD-L1+ and CD24hiCD38hiPD-L1+ B cells) increased significantly after treatment in good responder patients, although the frequency of total CD24hiCD38hi B cells decreased. CD19+ B cells from untreated RA patients and HC upregulated PD-L1 expression similarly upon stimulation with CpG plus IL-2 and were able to suppress, in vitro, CD8+ T cell proliferation and cytokine production in a PD-L1-dependent manner. Conclusions: Our results show that PD-L1+ B cells exhibiting T cell suppressive capacity are significantly decreased in untreated RA patients but increase in response to successful treatment. PD-L1 expression on B cells from RA patients can be modulated in vitro and PD-L1+ B cells could thus provide new perspectives for future treatment strategies.