RESUMO
Sodium selenite modulates the activity of lymphocytes. It negatively regulates the suppressive activity of cells and increases the immune response. In this study, we evaluated whether the regulatory T cell differentiation was modulated by sodium selenite. The percentages of CD4+CD25+Foxp3+, CD4+CD25+, and CD4+CTLA-4+ cells in CD4+ T cells cultures stimulated with IL-2 and TGF-ß in the presence or absence of selenium, in the form of sodium selenite (2.0×10-6M), were evaluated by flow cytometry. The mRNA expression of TET2/3 enzymes and IL-10 was analyzed by RT-qPCR and the levels of IL-10 were measured by an ELISA. We observed a decrease in CD4+CD25+Foxp3+ and CD4+CTLA-4+ cells in presence of selenium. However, normal percentages were reached again after selenium removal. An increase in CD4+CTL4-4+ cells was detected in selenium-primed cell cultures in absence of IL-2 and TGF-ß. In addition, we observed a decrease in TET3 in presence of selenium. Finally, we observed an augment in IL-10 transcription and protein levels and relative expression of TET2 in cultures exposed to selenium. We suggest that selenium reversibly affects the regulatory T cell differentiation in vitro. Likewise, selenium may modulate Treg percentages promoting optimal immune responses and, at the same time, the expression of specific suppressor molecules.
Assuntos
Interleucina-10 , Selênio , Linfócitos T Reguladores/metabolismo , Selenito de Sódio/farmacologia , Selenito de Sódio/metabolismo , Antígeno CTLA-4/metabolismo , Selênio/farmacologia , Selênio/metabolismo , Interleucina-2/genética , Interleucina-2/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Diferenciação Celular , Fatores de Transcrição Forkhead/metabolismo , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/metabolismoRESUMO
OBJECTIVES: Genetic association studies on alopecia areata (AA) performed in various populations have shown heterogeneous results. The aim of the current review was to synthesize the results of said studies to estimate the impact of FAS, FASL, PTPN22, CTLA4 and IL2RA gene polymorphisms on AA susceptibility. DESIGN: A systematic literature search was conducted in the Medline, Web of Science, Scopus, EMBASE and LILACS databases. Studies published up to June 2020 were included. The results available in the grey literature including the Open Grey and Google Scholar databases were also used. The texts of potentially related studies were screened by individual reviewers. Evidence of publication bias was assessed using the Newcastle-Ottawa scale and the quality of evidence was assessed using the GRADE system. The quantitative synthesis was performed using the fixed effect model. RESULTS: Out of 1784 articles, we identified 18 relevant articles for the qualitative synthesis and 16 for the quantitative synthesis. In a study of rs2476601 polymorphism of PTPN22 gene, including 1292 cases and 1832 controls, a correlation was found with the risk of developing AA in the allelic model (OR1.49 [95% C:1.13-1.95]), the heterozygous codominant (OR1.44 [95% CI:1:19-1.76]) and dominant model (OR1.43 [95% CI:1.18-1.73]). No association was found between the presence of FASL, PTPN22, CTLA and IL2RA gene polymorphisms with AA susceptibility. CONCLUSIONS: The results suggest that the T allele of the single nucleoid polymorphism (SNP) rs2476601 in PTPN22 gene is a risk factor for developing alopecia areata. However, more robust studies defining the ethnic background of the population of origin are required, so that the risk identified in the present study can be validated. Additionally, a greater number of studies is necessary to evaluate the role of the FAS, FASL, PTPN22, CTLA4 and IL2RA genetic variants, given the heterogenous results found in the literature.
Assuntos
Alopecia em Áreas/genética , Antígeno CTLA-4/genética , Proteína Ligante Fas/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Receptor fas/genética , Alelos , Alopecia em Áreas/epidemiologia , Alopecia em Áreas/patologia , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
BACKGROUND: Regulatory T cells (Tregs) play a critical role during Mycobacterium tuberculosis (Mtb) infection, modulating host responses while neutralizing excessive inflammation. However, their impact on regulating host protective immunity is not completely understood. Here, we demonstrate that Treg cells abrogate the in vitro microbicidal activity against Mtb. METHODS: We evaluated the in vitro microbicidal activity of peripheral blood mononuclear cells (PBMCs) from patients with active tuberculosis (TB), individuals with latent tuberculosis infection (LTBI, TST+/IGRA+) and healthy control (HC, TST-/IGRA-) volunteers. PBMCs, depleted or not of CD4+CD25+ T-cells, were analyzed to determine frequency and influence on microbicidal activity during in vitro Mtb infection with four clinical isolates (S1, S5, R3, and R6) and one reference strain (H37Rv). RESULTS: The frequency of CD4+CD25highFoxP3+ cells were significantly higher in Mtb infected whole blood cultures from both TB patients and LTBI individuals when compared to HC. Data from CD4+CD25+ T-cells depletion demonstrate that increase of CD4+CD25highFoxP3+ is associated with an impairment of Th-1 responses and a diminished in vitro microbicidal activity of LTBI and TB groups. CONCLUSIONS: Tregs restrict host anti-mycobacterial immunity during active disease and latent infection and thereby may contribute to both disease progression and pathogen persistence.
Assuntos
Atividade Bactericida do Sangue , Antígenos CD4/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Tuberculose Latente/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/imunologia , Antígenos CD4/genética , Estudos de Casos e Controles , Fatores de Transcrição Forkhead/genética , Humanos , Subunidade alfa de Receptor de Interleucina-2/genética , Linfócitos T ReguladoresRESUMO
BACKGROUND: The treatment of latent tuberculosis infection (LTBI) in individuals at risk of reactivation is essential for tuberculosis control. However, blood biomarkers associated with LTBI treatment have not been identified. METHODS: Blood samples from tuberculin skin test (TST) reactive individuals were collected before and after one and six months of isoniazid (INH) therapy. Peripheral mononuclear cells (PBMC) were isolated, and an in-house interferon-γ release assay (IGRA) was performed. Expression of chemokine ligand 4 (CCL4), chemokine ligand 10 (CXCL10), chemokine ligand 11 (CXCL11), interferon alpha (IFNA), radical S-adenosyl methionine domain-containing 2 (RSAD2), ubiquitin-specific peptidase 18 (USP18), interferon-induced protein 44 (IFI44), interferon-induced protein 44 like (IFI44L), interferon-induced protein tetratricopeptide repeats 1(IFIT1), and interleukin 2 receptor subunit alpha (IL2RA) mRNA levels were assessed by qPCR before, during, and after INH treatment. RESULTS: We observed significantly lower relative abundances of USP18, IFI44L, IFNA, and IL2RA transcripts in PBMC from IGRA-positive individuals compared to levels in IGRA-negative individuals before INH therapy. Also, relative abundance of CXCL11 was significantly lower in IGRA-positive than in IGRA-negative individuals before and after one month of INH therapy. However, the relative abundance of CCL4, CXCL10, and CXCL11 mRNA was significantly decreased and that of IL2RA and USP18 significantly increased after INH therapy, regardless of the IGRA result. Our results show that USP18, IFI44L, IFIT1, and IL2RA relative abundances increased significantly, meanwhile the relative abundance of CCL4, CXCL11, and IFNA decreased significantly after six months of INH therapy in TST-positive individuals. CONCLUSIONS: Changes in the profiles of USP18, IL2RA, IFNA, CCL4, and CXCL11 expressions during INH treatment in TST-positive individuals, regardless of IGRA status, are potential tools for monitoring latent tuberculosis treatment.
Assuntos
Expressão Gênica , Subunidade alfa de Receptor de Interleucina-2/genética , Tuberculose Latente/genética , Tuberculose Latente/microbiologia , Ubiquitina Tiolesterase/genética , Adulto , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Biomarcadores , Feminino , Humanos , Testes de Liberação de Interferon-gama , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Isoniazida/farmacologia , Isoniazida/uso terapêutico , Tuberculose Latente/diagnóstico , Tuberculose Latente/tratamento farmacológico , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , Pessoa de Meia-Idade , Teste Tuberculínico , Ubiquitina Tiolesterase/metabolismo , Adulto JovemRESUMO
AIM: To investigate the impact of physical fitness on the mobilization of CD4+ CD25 - CD39 + and CD4 + CD25 + CD39 + T cells in response to acute exercise. METHODS: Fifteen high physical fitness (25.3 ± 1.4 years) and 15 low physical fitness (26.1 ± 1.9 years) men performed a single bout of high-intensity interval exercise (HIIE, 10 bouts of 60 seconds at 85% HRmax intercepted by 75 seconds of recovery at 50% HRmax). Blood lymphocytes were isolated before, immediately after and 1 hour after exercise for assessment of cell surface expression of CD25, CD39, and CD73 on CD4+ T cells. Effector memory T cells (mTeff) were identified by CD4 + CD25 - CD39 + coexpression, and memory regulatory T cells (mTReg) were defined as CD4 + CD25 + CD39 + T cells. RESULTS: Exercise increased CD4+ and CD4 + CD25 + T cell frequencies immediately after followed by a decrease bellow to baseline values at 1 hour after the bout in both low and high physical fitness groups. At baseline, the proportions of mTeff were higher, while mTreg were lower in low physical fitness individuals. The frequency of mTreg increased immediately after HIIE in both groups, and remained higher 1 hour after the bout. However, high physical fitness individuals presented higher mTreg frequency in all periods evaluated. A significantly mobilization of mTeff cells was identified in both groups immediately after HIIE. High physical fitness individuals displayed a decrease in mTeff cells bellow to baseline, while the frequency of mTeff remained higher in low physical fitness group 1 hour after the bout. The peripheral frequency of CD4 + CD25 + CD73 + T cells increased in a similar way immediately after the bout in both groups, returning to the baseline values 1 hour after exercise. No differences in CD4 + CD25 - CD73 + T cells were observed after HIIE in both groups. CONCLUSION: Our results highlight the impact of physical activity status in the redistribution of CD4+ T cells expressing ectonucleotidases in response to HIIE.
Assuntos
5'-Nucleotidase/genética , Apirase/genética , Subunidade alfa de Receptor de Interleucina-2/genética , Aptidão Física/fisiologia , Linfócitos T Citotóxicos/metabolismo , Linfócitos T Reguladores/metabolismo , 5'-Nucleotidase/imunologia , Adulto , Apirase/imunologia , Antígenos CD4/genética , Antígenos CD4/imunologia , Exercício Físico , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/imunologia , Regulação da Expressão Gênica , Humanos , Memória Imunológica/genética , Imunofenotipagem , Subunidade alfa de Receptor de Interleucina-2/imunologia , Contagem de Linfócitos , Masculino , Linfócitos T Citotóxicos/citologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Reguladores/citologia , Linfócitos T Reguladores/imunologiaRESUMO
BACKGROUND Leprosy is a chronic infectious disease caused by Mycobacterium leprae, and compromises the skin and peripheral nerves. This disease has been classified as multibacillary (MB) or paucibacillary (PB) depending on the host immune response. Genetic epidemiology studies in leprosy have shown the influence of human genetic components on the disease outcomes. OBJECTIVES We conducted an association study for IL2RA and TGFB1 genes with clinical forms of leprosy based on two case-control samples. These genes encode important molecules for the immunosuppressive activity of Treg cells and present differential expressions according to the clinical forms of leprosy. Furthermore, IL2RA is a positional candidate gene because it is located near the 10p13 chromosome region, presenting a linkage peak for PB leprosy. METHODS A total of 885 leprosy cases were included in the study; 406 cases from Rondonópolis County (start population), a hyperendemic region for leprosy in Brazil, and 479 cases from São Paulo state (replication population), which has lower epidemiological indexes for the disease. We tested 11 polymorphisms in the IL2RA gene and the missense variant rs1800470 in the TGFB1 gene. FINDINGS The AA genotype of rs2386841 in IL2RA was associated with the PB form in the start population. The AA genotype of rs1800470 in TGFB1 was associated with the MB form in the start population, and this association was confirmed for the replication population. MAIN CONCLUSIONS We demonstrated, for the first time, an association data with the PB form for a gene located on chromosome 10. In addition, we reported the association of TGFB1 gene with the MB form. Our results place these genes as candidates for validation and replication studies in leprosy polarisation.
Assuntos
Predisposição Genética para Doença , Subunidade alfa de Receptor de Interleucina-2/genética , Hanseníase Multibacilar/genética , Hanseníase Paucibacilar/genética , Fator de Crescimento Transformador beta1/genética , Adulto , Alelos , Brasil , Estudos de Casos e Controles , Feminino , Humanos , Masculino , FenótipoRESUMO
Manifestations of Leishmania infantum infection range from asymptomatic to symptomatic visceral leishmaniasis (VL). People with symptomatic VL (sVL) have suppressed immune responses against Leishmania antigens that are reversed after clinical cure. The intradermal leishmanin skin test (LST) is negative during sVL, but it becomes positive after treatment. The aim of this study was to compare T cell responses in individuals with sVL, recovered VL (RecVL), and endemic controls. Endemic controls were household contacts of a VL case and they were grouped by their LST results, either positive (LST+) or negative (LST-). Mononuclear cells were studied ex vivo or after stimulation with soluble Leishmania antigens (SLA); cell surface markers and cytokines were determined. T cells, ex vivo, from individuals with sVL and from LST+ individuals presented a higher activation for CD4+ and CD8+ cells expressing CD69. However, lymphocytes from sVL stimulated with SLA had lower percentages of CD4+ and CD8+ cells expressing CD69 and CD8+ cells expressing CD25, with no release of interferon-γ or tumor necrosis factor. sVL subjects had lower percentage of memory cells (CD4+ CD45RO+), ex vivo, without SLA stimulation than RecVL, LST+, or LST- (P = 0.0022). However, individuals with sVL had fewer regulatory cells after SLA stimulation (CD4+ CD25HIGH, P = 0.04 and CD4+ FOXP3+, P = 0.02) than RecVL. The decrease in specific memory and activated CD4+ and CD8+ cells, as in response to Leishmania antigens, could explain, in part, the immune impairment during sVL. Finally, protective T cell responses are long lasting because both RecVL or LST+ individuals maintain a specific protective response to Leishmania years after the primary infection.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunidade Celular , Memória Imunológica , Leishmania infantum/imunologia , Leishmaniose Visceral/imunologia , Adolescente , Adulto , Idoso , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos T/genética , Antígenos de Diferenciação de Linfócitos T/imunologia , Antígenos de Protozoários/farmacologia , Doenças Assintomáticas , Brasil , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/parasitologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/parasitologia , Estudos de Casos e Controles , Criança , Feminino , Expressão Gênica , Humanos , Interferon gama/genética , Interferon gama/imunologia , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/imunologia , Lectinas Tipo C/genética , Lectinas Tipo C/imunologia , Leishmania infantum/crescimento & desenvolvimento , Leishmaniose Visceral/genética , Leishmaniose Visceral/parasitologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Testes Cutâneos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologiaRESUMO
Adoptive transfer of CD4+CD25+FOXP3+ regulatory T cells (Treg cells) has been successfully utilized to treat graft versus host disease and represents a promising strategy for the treatment of autoimmune diseases and transplant rejection. The aim of this study was to evaluate the effects of all-trans retinoic acid (atRA) and rapamycin (RAPA) on the number, phenotype, homing markers expression, DNA methylation, and function of induced human Treg cells in short-term cultures. Naive T cells were polyclonally stimulated and cultured for five days in the presence of different combinations of IL-2, TGF-ß1, atRA and RAPA. The resulting cells were characterized by the expression of FOXP3, activation, surface and homing markers. Methylation of the Conserved Non-coding Sequence 2 was also evaluated. Functional comparison of the different culture conditions was performed by suppression assays in vitro. Culturing naive human T cells with IL-2/TGFß1 resulted in the generation of 54.2% of Treg cells (CD4+CD25+FOXP3+) whereas the addition of 100 nM atRA increased the yield of Treg cells to 66% (p = 0.0088). The addition of RAPA did not increase the number of Treg cells in any of these settings. Treg cells generated in the presence of atRA had an increased expression of the ß7 integrin to nearly 100% of the generated Treg cells, while RAPA treated cells showed enhanced expression of CXCR4. The differential expression of homing molecules highlights the possibility of inducing Treg cells with differential organ-specific homing properties. Neither atRA nor RAPA had an effect on the highly methylated CNS2 sites, supporting reports that their contribution to the lineage stability of Treg cells is not mediated by methylation changes in this locus. Treg cells generated in the presence of RAPA show the most potent suppression effect on the proliferation of effector cells.
Assuntos
Sirolimo/farmacologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Tretinoína/farmacologia , Adolescente , Adulto , Antineoplásicos/farmacologia , Células Cultivadas , Ilhas de CpG/genética , Metilação de DNA/efeitos dos fármacos , Sinergismo Farmacológico , Citometria de Fluxo , Fatores de Transcrição Forkhead/genética , Fatores de Transcrição Forkhead/imunologia , Fatores de Transcrição Forkhead/metabolismo , Humanos , Interleucina-2/farmacologia , Subunidade alfa de Receptor de Interleucina-2/genética , Subunidade alfa de Receptor de Interleucina-2/imunologia , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Adulto JovemRESUMO
CD4 T cell activation and differentiation mechanisms constitute a complex and intricate signaling network involving several regulatory proteins. IRF2BP2 is a transcriptional repressor that is involved in gene-expression regulation in very diverse biologic contexts. Information regarding the IRF2BP2 regulatory function in CD4 T lymphocytes is very limited and suggests a role for this protein in repressing the expression of different cytokine genes. Here, we showed that Irf2bp2 gene expression was decreased in CD4 T cells upon activation. To investigate the possible regulatory roles for IRF2BP2 in CD4 T cell functions, this protein was ectopically expressed in murine primary-activated CD4 T lymphocytes through retroviral transduction. Interestingly, ectopic expression of IRF2BP2 led to a reduction in CD25 expression and STAT5 phosphorylation, along with an impaired proliferative capacity. The CD69 expression was also diminished in IRF2BP2-overexpressing cells, whereas CD44 and CD62L levels were not altered. In vivo, transferred, IRF2BP2-overexpressing, transduced cells displayed an impaired expansion capacity compared with controls. Furthermore, overexpression of IRF2BP2 in differentiated Th cells resulted in slightly reduced IL-4 and pro-TGF-ß production in Th2 and iTregs but had no effect on IFN-γ or IL-17 expression in Th1 and Th17 cells, respectively. Taken together, our data suggest a role for IRF2BP2 in regulating CD4 T cell activation by repressing proliferation and the expression of CD25 and CD69 induced by TCR stimuli.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Ativação Linfocitária/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Fatores de Transcrição/imunologia , Animais , Antígenos CD/biossíntese , Antígenos CD/genética , Antígenos de Diferenciação de Linfócitos T/biossíntese , Antígenos de Diferenciação de Linfócitos T/genética , Apoptose/imunologia , Células Cultivadas , Citocinas/biossíntese , Citocinas/genética , Feminino , Regulação da Expressão Gênica/imunologia , Humanos , Subunidade alfa de Receptor de Interleucina-2/biossíntese , Subunidade alfa de Receptor de Interleucina-2/genética , Lectinas Tipo C/biossíntese , Lectinas Tipo C/genética , Ativação Linfocitária/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Quimera por Radiação , Proteínas Recombinantes de Fusão/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução GenéticaRESUMO
Autoantibodies against the M2 receptors (M2AChR) have been associated with Dilated Cardiomyopathy (DCM). In the heart, P2×7 receptors influence electrical conduction, coronary circulation and response to ischemia. They can also trigger pro-inflammatory responses and the development of neurological, cardiac and renal disorders. Here, P2×7(-/-) mice displayed an increased heart rate and ST segment depression, but similar exercise performance when compared to wild type (WT) animals. After immunization with plasmid containing M2AChR cDNA sequence, WT mice produced anti-M2AChR antibodies, while P2×7(-/-) mice showed an attenuated production. Despite this, WT and P2×7(-/-) showed left ventricle cavity enlargement and decreased exercise tolerance. Transfer of serum from M2AChR WT immunized mice to näive recipients led to an alteration in heart shape. P2×7(-/-) mice displayed a significant increase in the frequency of spleen regulatory T cells population, which is mainly composed by the FoxP3(+)CD25(-) subset. M2AChR WT immunized mice showed an increase in IL-1ß, IFNγ and IL-17 levels in the heart, while P2×7(-/-) group produced lower amounts of IL-1ß and IL-17 and higher amounts of IFNγ. These results pointed to previously unnoticed roles of P2×7 in cardiovascular and immune systems, and underscored the participation of IL-17 and IFNγ in the progress of autoimmune DCM.