RESUMO
BACKGROUND: Fidaxomicin (FDX) has received considerable attention as a novel therapeutic alternative agent to vancomycin (VCM) for Clostridioides difficile infection (CDI). However, the superiority and efficacy profile of FDX are not sufficiently determined by high-quality evidence. This study aimed to clarify the superiority of FDX for CDI treatment through a systematic review and meta-analysis. METHODS: We conducted a meta-analysis of randomized controlled trials (RCTs) which evaluated the efficacy and safety of FDX and VCM in patients with CDI. Electronic databases (PubMed, Cochrane Library, Web of Science, and Clinicaltrials.gov) were searched for studies published until October 15, 2021. The primary endpoint was global cure. The secondary endpoints were clinical cure, recurrence, and adverse event. Risk ratios (RRs), risk differences (RDs), and 95% confidence intervals were calculated using Mantel-Haenszel random-effects model. The risk of bias was assessed using Cochrane Handbook for Systematic Reviews of Interventions and Assessment Criteria. RESULTS: Six RCTs were included in this meta-analysis. Compared to VCM, FDX was associated with significantly higher global cure rates (RR = 1.18, P < 0.00001; RD = 0.11, 95% CI = 0.07-0.16). In addition, clinical cure rates were comparable between FDX and VCM (P = 0.31). FDX was associated with significantly lower recurrence rates compared to VCM (RR = 0.59, P < 0.0001). In addition, adverse event rates were not significantly different between the drugs (P = 0.41). CONCLUSION: FDX achieves significantly higher global cure rates and lower recurrence rates and is comparable to VCM in clinical cure rates and adverse event rates in patients with CDI. Collectively, FDX is superior to VCM as a therapeutic agent for CDI.
Assuntos
Clostridioides difficile , Infecções por Clostridium , Antibacterianos/efeitos adversos , Infecções por Clostridium/tratamento farmacológico , Fidaxomicina/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Vancomicina/efeitos adversosRESUMO
OBJECTIVES: B cell depletion by rituximab (RTX) is an effective treatment for anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV). However, peripheral B cell phenotypes and the selection criteria for RTX therapy in AAV remain unclear. METHODS: Phenotypic characterization of circulating B cells was performed by 8-color flow cytometric analysis in 54 newly diagnosed AAV patients (20 granulomatosis with polyangiitis and 34 microscopic polyangiitis). Patients were considered eligible to receive intravenous cyclophosphamide pulse (IV-CY) or RTX. All patients also received high-dose glucocorticoids (GC). We assessed circulating B cell phenotypes and evaluated the efficacy after 6 months of treatment. RESULTS: There were no significant differences in the rate of clinical improvement, relapses, or serious adverse events between patients receiving RTX and IV-CY. The rate of Birmingham Vasculitis Activity Score (BVAS) improvement at 6 months tended to be higher in the RTX group than in the IV-CY group. The proportion of effector or class-switched memory B cells increased in 24 out of 54 patients (44%). The proportions of peripheral T and B cell phenotypes did not correlate with BVAS at baseline. However, among peripheral B cells, the proportion of class-switched memory B cells negatively correlated with the rate of improvement in BVAS at 6 months after treatment initiation (r = - 0.28, p = 0.04). Patients with excessive B cell differentiation were defined as those in whom the proportion of class-switched memory B cells or IgD-CD27- B cells among all B cells was > 2 SDs higher than the mean in the HCs. The rate of BVAS remission in patients with excessive B cell differentiation was significantly lower than that in patients without. In patients with excessive B cell differentiation, the survival rate, the rate of BVAS-remission, and dose reduction of GC were significantly improved in the RTX group compared to those in the IV-CY group after 6 months of treatment. CONCLUSIONS: The presence of excessive B cell differentiation was associated with treatment resistance. However, in patients with circulating B cell abnormality, RTX was effective and increased survival compared to IV-CY. The results suggest that multi-color flow cytometry may be useful to determine the selection criteria for RTX therapy in AAV patients.
Assuntos
Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Poliangiite Microscópica , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/tratamento farmacológico , Diferenciação Celular , Ciclofosfamida/uso terapêutico , Humanos , Indução de Remissão , Rituximab/uso terapêutico , Resultado do TratamentoRESUMO
OBJECTIVE: The pathological changes in SSc include immune system dysregulation and microvascular damage. However, the association of immune cell phenotype heterogeneity and microvascular abnormalities is unclear. The aim of this study is to elucidate this association in SSc. METHODS: Peripheral blood mononuclear cells obtained from 150 SSc patients were used for comprehensive flow cytometric analysis based on the Human Immunology Project. Hierarchical cluster analysis was used to classify SSc patients into subgroups and their association with microvascular abnormalities, as assessed by nailfold videocapillaroscopy (i.e. 'early', 'active' and 'late' patterns), was analysed. RESULTS: The proportions of activated CD4+ T cells, T cells re-expressing CD45RA, activated Th1 and Th17 cells and IgD-CD27- B cells were higher in SSc patients than in healthy individuals. Hierarchical cluster analysis stratified SSc patients into three groups: patients with few immune abnormalities (fewer abnormalities group), patients with high proportions of activated T and Treg cells (Treg-dominant group) and patients with high proportions of Tfh and plasmablasts (Tfh-dominant group). Age and disease duration were comparable among the groups. On the other hand, microvascular abnormalities, especially the 'late' nailfold videocapillaroscopy pattern, correlated with internal organ involvement. Among the groups stratified according to immune cell phenotype, the progression to the 'late' nailfold videocapillaroscopy pattern was more frequent in the Tfh-dominant group. CONCLUSION: Our study confirmed the presence of immunophenotypic abnormalities in SSc. Immunological abnormalities were not uniform but rather limited to subpopulations, particularly the Tfh-dominant group, where they were highly associated with microvascular abnormalities and organ involvement.
Assuntos
Linfócitos B/imunologia , Capilares/patologia , Imunidade Celular , Leucócitos Mononucleares/imunologia , Angioscopia Microscópica/métodos , Unhas/irrigação sanguínea , Escleroderma Sistêmico/imunologia , Linfócitos B/patologia , Feminino , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/patologia , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Fenótipo , Escleroderma Sistêmico/patologiaRESUMO
Objective Type 2 diabetes mellitus (T2DM) and rheumatoid arthritis (RA) are both complicated by arteriosclerosis, resulting in increased rates of cardiovascular events. No previous studies have compared the index between RA and T2DM. We assessed the vascular endothelial function in early-stage arteriosclerosis for each disease to determine the influential factors and compared the extent to which these two diseases cause vascular endothelial dysfunction. Methods This study is a retrospective study based on medical records. Differences in the reactive hyperemia index (RHI) among the groups and factors affecting the RHI in each group was analyzed. The vascular endothelial function was assessed by measuring the RHI using peripheral arterial tonometry. Patients The study subjects were 114 patients with non-functional thyroid tumors (healthy n=14), T2DM (T2DM n=64), and RA (RA n=36). Results The RHI was 2.29 in the control, 1.85 in the T2DM, and 1.83 in the RA group, with values lower in the T2DM and RA groups than in the control group (p=0.033) but not markedly different between the two disease groups. The RHI distribution (<1.68/1.68 to <2.10/≥2.1) was as follows: control group: 14.3%/28.6%/57.1%; T2DM group: 42.2%/39.1%/18.8%; and RA group: 36.1%/44.4%/19.4% (p=0.031), respectively. A multivariate analysis identified the triglyceride level and dyslipidemia in the control group and the Disease Activity Score in 28 joints with the erythrocyte sedimentation rate and fasting plasma glucose level in the RA group to influence the RHI. Conclusion The vascular endothelial function was impaired in approximately 80% of patients with T2DM and RA, with comparable degrees of impairment between the two diseases. No factors affecting the function were identified in the T2DM group, while the function was more impaired in patients with a higher disease activity in the RA group.
Assuntos
Arteriosclerose/fisiopatologia , Artrite Reumatoide/fisiopatologia , Diabetes Mellitus Tipo 2/fisiopatologia , Endotélio Vascular/fisiopatologia , Hiperemia/fisiopatologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Manometria/métodos , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
Objectives: We sought to investigate the selection of specific biological DMARDs (bDMARDs) based on characteristic lymphocyte phenotypes for treating PsA. Methods: Of 64 patients with PsA resistant to MTX, 26 underwent bDMARDs therapy selected according to phenotypic differences in peripheral helper T cells on 8-colour flow cytometry. The efficacies of this strategic treatment and the standard treatment administered to the other 38 patients were evaluated at 6 months. Results: The 26 patients with PsA in the strategic treatment group were classified into the following four types based on peripheral blood analysis: (i) CXCR3+CCR6-CD38+HLA-DR+ activated Th1 cell-predominant type, (ii) CXCR3-CCR6+ CD38+HLA-DR+ activated Th17 cell-predominant type, (iii) Th1/Th17-high type and (iv) Th1/Th17-low type. Accordingly, ustekinumab was administered to the activated Th1 cell-predominant patients, secukinumab to the activated Th17 cell-predominant patients, secukinumab or TNF inhibitor to the Th1/Th17-high patients, and TNF inhibitor to the Th1/Th17-low patients. After 6 months of strategic treatment, there was a significant decrease in simplified disease activity index (SDAI) (from 16.2 to 3.52), DAS28 (ESR) (from 4.13 to 2.27) and psoriasis area and severity index (from 8.36 to 2.40). Low disease activity by SDAI was achieved in 24 (92.3%) of the 26 patients. The rate of low disease activity achievement according to SDAI at 6 months was significantly higher in the strategic bDMARDs treatment group compared with that of the standard bDMARDs treatment group. Conclusion: Strategic treatment in which different bDMARDs were selected according to phenotypic differences in helper T cells showed significantly higher efficacy than standard bDMARD therapy, indicating the value of precision medicine.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Psoriásica/tratamento farmacológico , Produtos Biológicos/uso terapêutico , Medicina de Precisão/métodos , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Idoso , Artrite Psoriásica/imunologia , Feminino , Citometria de Fluxo/métodos , Humanos , Imunofenotipagem , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Células Th1/imunologia , Células Th17/imunologiaRESUMO
Memory B cells are increased in systemic lupus erythematosus (SLE) cases, but the qualitative abnormalities and induction mechanism of these cells are unclear. Here, we subclassified B cells by their chemokine receptor expression and investigated their induction mechanism. The peripheral blood of patients with SLE showed higher levels of CXCR5- and CXCR3+ B cells. CXCR5-CXCR3+ B cell levels were elevated in patients with active SLE, which decreased with improving disease conditions. Interferon (IFN)-γ stimulation increased CXCR3 expression, whereas IFN-ß stimulation reduced CXCR5 expression in B cells. Furthermore, CXCR5-CXCR3+ B cells were induced by a combination of IFN-ß and IFN-γ stimulation. Renal tissue examination of patients with active lupus nephritis confirmed the presence of CD19+CXCR3+ B cells. Collectively, the results revealed qualitative abnormalities accompanying reduced CXCR5 expression via type I IFN and enhanced CXCR3 expression via type II IFN in SLE, suggesting their involvement in B cell infiltration into tissues and inflammatory pathogenesis.
Assuntos
Linfócitos B/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Receptores CXCR3/metabolismo , Receptores CXCR5/metabolismo , Adolescente , Adulto , Idoso , Antígenos CD19/metabolismo , Artrite Reumatoide/imunologia , Artrite Reumatoide/metabolismo , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Memória Imunológica/imunologia , Interferon beta/imunologia , Interferon beta/farmacologia , Interferon gama/imunologia , Interferon gama/farmacologia , Lúpus Eritematoso Sistêmico/imunologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Quimiocinas/metabolismo , Índice de Gravidade de Doença , Adulto JovemRESUMO
OBJECTIVES: T follicular helper (Tfh) cells are critical in the development and progression of systemic lupus erythematosus (SLE). To assess the characteristics and mechanisms of differentiation of Tfh cells, we investigated the phenotype of T helper cells in patients with SLE and underlying epigenetic modifications by cytokine-induced signal transducer and activators of transcription (STAT) family factors. METHODS: Peripheral blood mononuclear cells from patients and healthy donors were analysed by flow cytometry. CD4+ T cells were isolated and cultured under various stimulations. Expression of characteristic markers and phosphorylation of STATs were analysed by flow cytometry and quantitative PCR. Histone modifications were analysed by chromatin immunoprecipitation (ChIP)-PCR. RESULTS: Differentiation of CD4+CXCR5+CXCR3+Bcl-6+T-bet+IL-21+IFN-γ+Tfh-Th1-like cells was induced by interleukin (IL)-12-induced activation of STAT1 and STAT4 simultaneously. The loci of Bcl-6 and T-bet at STAT binding sites were marked by bivalent histone modifications. After IL-12 stimulation, both STAT1 and STAT4 directly bound on BCL6 and TBX21 gene loci accompanied by suppression of repressive histone mark trimethylated histone 3 lysine 27. Levels of serum IL-12 and interferon (IFN)-γ, expression of IL-12 receptors and proportion of CXCR5+CXCR3+ activated Tfh-Th1-like cells were increased in patients with SLE. Furthermore, the level of pSTAT1, pSTAT4 and T-bet were higher in activated Tfh-Th1-like cells than non-Tfh-Th1 cells. CONCLUSION: Our findings suggest that IL-12-mediated co-activation of STAT1 and STAT4 alters histone modification, resulting in differentiation of Tfh-Th1-like cells that are characteristically expanded in patients with SLE. This could be one of the underlying mechanisms responsible for expansion of Tfh-Th1-like cells and potentially helpful towards development of cell-specific treatment for SLE.
Assuntos
Epigênese Genética/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Fatores de Transcrição STAT/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Estudos de Casos e Controles , Diferenciação Celular/imunologia , Células Cultivadas , Feminino , Humanos , Imunofenotipagem , Interleucina-12/imunologia , Lúpus Eritematoso Sistêmico/genética , Masculino , Pessoa de Meia-Idade , Fosforilação/imunologia , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT4/imunologia , Subpopulações de Linfócitos T/imunologia , Adulto JovemRESUMO
Objective: The aim of this study was to assess the therapeutic effects of biological DMARDs (bDMARDs) on the diversity of immune cell phenotypes in peripheral blood of patients with RA. Methods: Peripheral immune cell phenotypes were determined in 108 RA patients who were non-responsive to conventional DMARDs and 33 healthy control subjects by eight-colour flow cytometry. We also examined the correlation between the phenotypes and clinical findings and assessed the effects of 24-week treatment with bDMARDs. Results: The proportions of T follicular helper (Tfh) cells, IgD- CD27- double negative B cells and plasmacytoid dendritic cells (pDCs) were higher in patients with active RA than in healthy control. The percentages of memory T cells, Th17 and Tfh cells correlated with autoantibody titres, whereas that of plasmablasts correlated with disease activity scores. Treatment with TNF inhibitors reduced the proportion of pDCs, while tocilizumab reduced the proportion of double-negative B cells but increased naïve and activated Treg cells. Abatacept treatment resulted in marked decrease in the proportion of activated Tfh but slightly reduced Th17 and Treg cells. The proportion of Tfh cells was an independent and significant predictor of the response to abatacept therapy. Conclusion: Molecular targeted therapies induced different changes in different immune cell phenotypes. Among the phenotypes, Tfh cells seem a potential target for abatacept. Immunophenotypic analysis might be useful for prediction of the response to bDMARDs.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Linfócitos B/imunologia , Células Dendríticas/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Abatacepte/uso terapêutico , Adalimumab/uso terapêutico , Idoso , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Estudos de Casos e Controles , Certolizumab Pegol/uso terapêutico , Etanercepte/uso terapêutico , Feminino , Humanos , Imunoglobulina D/imunologia , Imunofenotipagem , Infliximab/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Subpopulações de Linfócitos T/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidoresRESUMO
B cells play a pivotal role in the initiation and perpetuation of SLE. Because SLE is molecularly and clinically heterogeneous, efficacious targeted therapy to clinical remission has not yet been established in SLE. We have found i) statistical clustering between Tfh cells and class-switched memory B cells and the upregulated transition from CXCR5+ IgM memory B cells to CXCR3+ class-switched memory B cells in SLE by 8-color flow cytometry, ii) the involvement of Syk, Btk and JAK in the activation and differentiation of B cells in SLE, iii) SLE patients was divided to 3 groups based on immunophenotypic analysis and statistical analysis and patients in the Tfh/class-switched B cell-dominant group were most refractory to conventional therapies although 3 groups had similar clinical features. Thus, novel therapies targeting Tfh-memory B cell interaction are anticipated in certain subpopulation of SLE patients, which leads to the precision medicine in SLE.
Assuntos
Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Anticorpos/imunologia , Humanos , Fenótipo , Transdução de Sinais , Subpopulações de Linfócitos T/imunologiaRESUMO
Objective: To assess the role of an abnormal immune network in the pathology of IgG4-related disease (IgG4-RD). Methods: Sixteen patients diagnosed with IgG4-RD at our institution were selected. Peripheral immunocompetent cells were immunophenotyped by multicolour flow cytometry to assess the association between clinical manifestation and pathological findings. Results: Compared with healthy controls, IgG4-RD patients showed comparable proportions of Th1 and Th17 cells, but higher proportions of Treg and follicular helper T (Tfh) cells. Further, the proportions of class-switched memory B cells and plasmablasts were higher in patients. Among all phenotypes, in particular, the plasmablast proportion increased from 4.2% (controls) to 16.5% (patients). The serum IgG levels were found to be correlated with the proportions of plasmablasts and Tfh cells, but not with those of other T cell subsets. In patients with extraglandular symptoms, only plasmablasts, Tfh cells and memory Treg cells were increased. Histopathological examination revealed a marked Tfh (CD4+ Bcl6+) cell infiltration; the increase of Tfh cells in the peripheral blood thus reflected the degree of Tfh cell infiltration into the tissue. Although steroid therapy reduced plasmablast and Tfh cell proportions, the memory Treg cell proportion remained unchanged. Conclusion: The association found between Tfh cells and plasmablasts, linked with biological plausibility, suggests that Tfh cells contribute to the pathogenesis of IgG4-RD. Our results also suggested that controlling the Tfh cell-plasmablast axis could be a novel therapeutic strategy for treating IgG4-RD.
Assuntos
Doenças Autoimunes/imunologia , Imunoglobulina G/sangue , Paraproteinemias/imunologia , Plasmócitos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Idoso , Doenças Autoimunes/sangue , Linfócitos B/imunologia , Estudos de Casos e Controles , Feminino , Citometria de Fluxo , Humanos , Switching de Imunoglobulina , Imunofenotipagem , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Paraproteinemias/sangue , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologiaRESUMO
OBJECTIVE: To elucidate the diversity of systemic lupus erythematosus (SLE) based on immunophenotyping. METHODS: Peripheral blood mononuclear cells were obtained from 143 SLE patients and 49 healthy individuals. Circulating B, T, and dendritic cells were defined using flow cytometric analysis as recommended by the Human Immunology Project Consortium. Based on these results, immunophenotypes were distinguished by principal components analysis (PCA), and cluster analysis was used to classify SLE patients into subgroups. RESULTS: The proportions of Treg and follicular helper T (Tfh) cells were higher in SLE patients than in healthy controls, whereas Th1 and Th17 cell proportions did not differ. Proportions of class-switched memory B cells and IgD-CD27- B cells were increased in SLE patients as well. The largest difference compared to the control group was observed in the proportion of plasmablasts, which was higher in SLE patients and correlated with disease activity as assessed with the British Isles Lupus Assessment Group index. PCA indicated that the immunophenotype of SLE patients consisted of abnormalities of the T and B cell axes. Cluster analysis showed that the SLE patients could be stratified into 3 subgroups (with high proportions of plasmablasts in all groups): patients who did not show the characteristic features (T cell-independent group), patients with a high percentage of Tfh cells (Tfh-dominant group), and patients with a high percentage of memory Treg cells (Treg-dominant group). The percentage of patients whose SLE was resistant to treatment was highest among the Tfh-dominant group. CONCLUSION: Our study indicates that patients with active SLE can be divided into 3 subgroups based on T cell heterogeneity. Further immunophenotyping studies should help elucidate the pathogenesis of SLE and provide important information for the development of new therapies.
Assuntos
Subpopulações de Linfócitos B/imunologia , Linfócitos B/imunologia , Células Dendríticas/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Células Th1/imunologia , Células Th17/imunologia , Adulto , Análise por Conglomerados , Feminino , Citometria de Fluxo , Humanos , Imunoglobulina D/imunologia , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Plasmócitos/imunologia , Células Precursoras de Linfócitos B/imunologia , Análise de Componente Principal , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologiaRESUMO
UNLABELLED: A randomized controlled study of rituximab demonstrated that the drug protects pancreatic function in patients with acute-onset type 1 diabetes mellitus (AOT1DM). However, the mechanism of this protective effect is poorly understood. We examined the effects of rituximab in two patients with AOT1DM in the honeymoon period and the mechanism of these effects. Case 1 was a 40-year-old man and Case 2 was a 45-year-old man, both diagnosed with AOT1DM. Various tests indicated intact capacity for endogenous insulin secretion and that they were in the honeymoon phase of AOT1DM. Treatment with rituximab protected against pancreatic ß-cell damage and maintained somewhat the endogenous insulin secretion. In Case 2, HbA1c level was maintained below 6.5% up to 24 months after treatment. However, in Case 1, the patient showed a gradual increase in HbA1c level starting around 9 months but fell at 12 months to >9.0% and required an insulin dose about twice greater than that of Case 2. High spleen tyrosine kinase (Syk) levels were recorded in the two patients before rituximab administration and after the treatment, the levels were further increased in Case 1, but decreased in Case 2. Both patients require continuous careful follow-up for glycemic control, insulin secretion capacity, and adverse reactions in the future. Although the clinical relevance of high Syk levels in AOT1DM patients remains unclear, the difference in the change in Syk level between the two patients may explain the different clinical courses. LEARNING POINTS: We described the pancreas-protective effect of rituximab in two patients with acute-onset type 1 diabetes mellitus in the honeymoon period and investigated the possible mechanism of action.The present study demonstrated that treatment with rituximab maintained endogenous insulin secretion capacity for 2 years in the two patients.The phosphorylated-spleen tyrosine kinase (p-Syk) data suggest that the differences in HbA1c level and the required insulin dose between the two patients could be due to reactivation or nonreactivation of ß-cells.
RESUMO
OBJECTIVE: B cells play an important role in the pathogenesis of autoimmune diseases. The role of Bruton's tyrosine kinase (Btk) in cytokine-induced human B cell differentiation and class-switch recombination remains incompletely defined. This study analysed the effect of Btk on human activated B cells. METHODS: Purified B cells from healthy subjects were stimulated with B cell receptor (BCR) and other stimuli with or without a Btk inhibitor and gene expression was measured. The B cell line BJAB was used to assess Btk-associated signalling cascades. Phosphorylated Btk (p-Btk) in peripheral blood B cells obtained from 10 healthy subjects and 41 patients with RA was measured by flow cytometry and compared with patient backgrounds. RESULTS: IL-21 signalling, in concert with BCR, CD40 and BAFF signals, led to robust expression of differentiation- and class-switch DNA recombination-related genes and IgG production in human B cells, all of which were significantly suppressed by the Btk inhibitor. Although phosphorylation of STAT1 and STAT3 was induced by co-stimulation with IL-21, BCR and CD40, STAT1 phosphorylation in the nucleus, but not in the cytoplasm, was exclusively impaired by Btk blockade. High levels of p-Btk were noted in B cells of RA patients compared with controls and they correlated significantly with titres of RF among RF-positive patients. CONCLUSION: The findings elucidate a model in which Btk not only plays a fundamental role in the regulation of BCR signalling, but may also mediate crosstalk with cytokine signalling pathways through regulation of IL-21-induced phosphorylation of STAT1 in the nuclei of human B cells. Btk appears to have pathological relevance in RA.
Assuntos
Fator Ativador de Células B/fisiologia , Linfócitos B/fisiologia , Antígenos CD40/fisiologia , Interleucinas/fisiologia , Proteínas Tirosina Quinases/fisiologia , Proteínas Proto-Oncogênicas c-bcr/fisiologia , Transdução de Sinais/fisiologia , Tirosina Quinase da Agamaglobulinemia , Idoso , Artrite Reumatoide/metabolismo , Artrite Reumatoide/patologia , Artrite Reumatoide/fisiopatologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Antígenos CD40/farmacologia , Estudos de Casos e Controles , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Feminino , Técnicas de Silenciamento de Genes , Humanos , Técnicas In Vitro , Interleucinas/farmacologia , Masculino , Pessoa de Meia-Idade , Fosforilação , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas c-bcr/farmacologia , Fator Reumatoide/metabolismo , Fator de Transcrição STAT1/metabolismoRESUMO
SLE is a systemic autoimmune disease characterized by overactivation of autoreactive memory B cells. However, little is known about the mechanism of qualitative abnormality of B cells. The subset classification of T cells by expression pattern of master transcription factors and chemokine receptors has been established. The biology of T cells is useful information to assess qualitative abnormality of B cells. Therefore, we focused on the expression of chemokine receptors such as CXCR5 and CXCR3 on B cells in order to define the B cell subset classification in patients with SLE. Our results revealed that pathological B cells, which lose CXCR5 and express CXCR3, might be involved in autoantibody production through the interaction with Tfh cells, and in acquisition of effector function of memory B cells during the pathological process in SLE. In addition, the results revealed that those effector B cells still remained after improvement of disease activity by immunosuppressive therapy, indicating that the quantitative abnormality, which is not improved by current therapy, may underlie in this disease.
Assuntos
Subpopulações de Linfócitos B/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Receptores de Quimiocinas/metabolismo , Autoanticorpos/biossíntese , Subpopulações de Linfócitos B/classificação , Subpopulações de Linfócitos B/metabolismo , Comunicação Celular , Humanos , Terapia de Imunossupressão , Lúpus Eritematoso Sistêmico/terapia , Linfócitos T/imunologia , Linfócitos T Auxiliares-Indutores/imunologiaRESUMO
OBJECTIVE: B cells play a pivotal role in the pathogenesis of autoimmune diseases. Although Syk functions as a key molecule in B cell receptor signaling, the pathologic role of Syk in B cells in rheumatoid arthritis (RA) remains unclear. The purpose of this study was to assess the relevance of activation of Syk in B cells to the pathologic development of RA and to the responsiveness of RA patients to treatment with biologics. METHODS: Healthy subjects (n = 36) and patients with moderate or severe RA disease activity (n = 70) were studied. The phosphorylation of Syk (pSyk) in peripheral blood B cells was measured by flow cytometry, and its correlation with clinical characteristics and changes after administration of biologic agents was evaluated. RESULTS: Levels of pSyk in peripheral blood B cells were preferentially higher in patients with RA compared to healthy subjects. Patients with significantly higher pSyk levels were strongly positive for anti-citrullinated protein antibodies (ACPAs). High pSyk levels were not correlated with the severity of disease activity. Treatment with abatacept, but not tumor necrosis factor inhibitors, significantly reduced the levels of pSyk in RA peripheral blood B cells. Abatacept also significantly reduced the proportion of follicular helper T (Tfh) cells. CONCLUSION: Levels of pSyk in peripheral blood B cells were significantly elevated in patients with RA, and these patients also exhibited strong positivity for ACPAs. These data suggest that abatacept seems to inhibit the phosphorylation of Syk in B cells, as well as the development of Tfh cells, thus highlighting the relevance of B cell-T cell interactions as a potential target of abatacept therapy in RA.
Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Linfócitos B/metabolismo , Imunoconjugados/uso terapêutico , Receptores Proteína Tirosina Quinases/metabolismo , Abatacepte , Idoso , Antirreumáticos/farmacologia , Artrite Reumatoide/patologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/patologia , Estudos de Casos e Controles , Comunicação Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Imunoconjugados/farmacologia , Masculino , Pessoa de Meia-Idade , Fosforilação/efeitos dos fármacos , Índice de Gravidade de Doença , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Linfócitos T Auxiliares-Indutores/patologia , Resultado do TratamentoRESUMO
The purpose of the present study was to compare facial expression recognition in individuals with schizophrenia and normal controls using the Noh Mask Test. Fifteen men with schizophrenia and 15 normal controls were presented with a photograph of a Noh mask rotated either upward or downward from the neutral front-facing position, and an emotion label, and were requested to judge whether the expression of the mask was congruent with the indicated emotion. Using multidimensional scaling, the facial expression of the Noh mask recognized by the patients and the healthy controls was analyzed in 3-D: (i) Rejection-Attention; (ii) Pleasant-Unpleasant; and (iii) Awakening-Relaxation. Individuals with schizophrenia had difficulty recognizing that others had intentions of harming them. The Noh Mask Test was found to be useful in discriminating between individuals with schizophrenia and controls in the recognition of facial expression (discriminant ratio: 99.9%).
Assuntos
Emoções , Expressão Facial , Testes Neuropsicológicos/estatística & dados numéricos , Reconhecimento Visual de Modelos , Esquizofrenia/diagnóstico , Psicologia do Esquizofrênico , Adulto , Diagnóstico Diferencial , Aprendizagem por Discriminação , Humanos , Masculino , Pessoa de Meia-Idade , Orientação , Psicometria/estatística & dados numéricos , Valores de ReferênciaRESUMO
This study investigated retrospectively the thoughts people had of World War II, especially the Battle of Okinawa at that time, and their current evaluation of their own wartime experience. A questionnaire survey was conducted, and 217 older adults, 114 women and 103 men between 65 and 88 years old, participated. Results indicated that men generally had more negative feelings than women at the end of the war. And psychological damages caused by traumatic war memories seemed to have persisted in not a few individuals in spite of over half a century since the end of the war. However, others had been more positive and accepting toward their wartime experiences. This difference appeared to be related to qualitative differences of various experiences, as well as the person's age. It is argued that a vigorous approach will be necessary for this sort of study of Japanese war victims from a number of viewpoints.