ABSTRACT
Objective:To investigate the effect of interleukin (IL)-7 receptor α (IL-7Rα) antibody on the immune inflammation and renal injury in MRL/lpr lupus mice.Methods:Fifteen 3-4-week-old female MRL/lpr lupus mice (specific pathogen free) weighing 15-16 g were bred to 14-week-old and randomly divided into three groups: IL-7Rα antibody intervention group, isotype antibody (positive control) group and normal saline (negative control) group. The mice in the threc groups were intraperitoneally injected with IL-7Rα antibody, isotype antibody and normal saline respectively, with 100 μg three times a week for 4 weeks. At the age of 18-week old, the mice were sacrificed. Twenty-four-hour urinary protein was detected by Coomassie brilliant blue method, serum creatinine was detected by peroxidase method, and the expression of autoantibody (anti-double strand DNA antibody) and inflammatory factors such as tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and IL-21 was detected by enzyme-linked immunosorbent assay method. Renal pathology was detected by PAS and Sirius red staining, and CD3 and F4/80 in renal tissues were detected by immunohistochemistry method. Regulatory T cells, follicullar helper T cells (Tfh) and follicular regulatory T cells (Tfr) were detected by flow cytometry.Results:The 24-hour urinary protein, serum creatinine, serum anti-double strand DNA antibody and serum IFN-γ and IL-21 in the IL-7Rα antibody intervention group were significantly lower than those in the control groups (all P<0.01). However, there was no significant difference in serum TNF-α among the three groups ( F=0.39, P>0.05). The positive infiltrating cells of CD3 and F4/F80, and the ratio of type Ⅰ/Ⅲ collagen fibers ( F=41.11, P<0.01) of renal tissues in the IL-7Rα antibody intervention group were lower than those in the other two groups. Compared with the control groups, the ratio of regulatory T cells (CD4 +CD25 +Foxp3 +)/effector T cells (CD4 +CD25 +) in blood of IL-7Rα antibody intervention group increased ( F=21.64, P<0.01), while the ratio of Tfr (CD4 +CXCR5 +Foxp3 +)/Tfh (CD4 +CXCR5 +) in peripheral blood and spleen increased ( F=38.95, P<0.01; F=12.90, P<0.01). Conclusion:IL-7Rα antibody can reduce the production of autoantibodies such as anti-double strand DNA antibody and inflammatory factors by increasing the ratio of regulatory T cells and Tfr/Tfh, thus alleviating immune inflammation and renal damage in MRL/lpr lupus mice.
ABSTRACT
Follicular regulatory T cells (Tfr) have critical functions in inflammatory and autoimmune disorders. The main purpose of the current work was to assess Tfr cell frequency in patients with dilated cardiomyopathy (DCM). Flow cytometry showed that, compared with normal controls, DCM cases showed markedly reduced Tfr cell rates and Tfr/Tfh ratios, but significantly increased follicular helper T cell (Tfh) rates. Correlation analysis showed that the Tfr rate in DCM patients was positively correlated with left ventricular ejection fraction (LVEF), and negatively correlated with N-terminal brain natriuretic peptide (NT-proBNP) levels. Lower Foxp3 and higher Bcl-6, ICOS, and PD-1 mRNA expression levels were found in patients with DCM. In addition, plasma interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-21 levels were significantly increased in DCM cases. Moreover, IgG and IgG3 levels were also elevated in individuals with DCM. Correlation analysis showed that the Tfr rate in DCM patients was negatively correlated with IgG and IgG3, while the Tfh rate was positively correlated with IgG and IgG3. Changes in circulating Tfr levels may have a critical immunomodulatory function in DCM and may become a new therapeutic target for DCM.
ABSTRACT
Myasthenia gravis(MG)is a B cell-mediated,T cell-dependent,complements-involved autoimmune disease.Ocular myasthenia gravis(OMG)is a typical MG,with its symptoms limited to the extraocular muscles.The occurrence and development of a variety of autoimmune diseases including OMG are closely associated with the imbalanced expression of follicular regulatory T cells(Tfr cells).Therefore,Tfr cells may be a new research topic for OMG.
Subject(s)
Humans , Complement System Proteins , Myasthenia Gravis , Oculomotor Muscles , T-Lymphocytes, RegulatoryABSTRACT
Follicular helper T (TFH) cells are recently highlighted as their crucial role for humoral immunity to infection as well as their abnormal control to induce autoimmune disease. During an infection, naive T cells are differentiating into TFH cells which mediate memory B cells and long-lived plasma cells in germinal center (GC). TFH cells are characterized by their expression of master regulator, Bcl-6, and chemokine receptor, CXCR5, which are essential for the migration of T cells into the B cell follicle. Within the follicle, crosstalk occurs between B cells and TFH cells, leading to class switch recombination and affinity maturation. Various signaling molecules, including cytokines, surface molecules, and transcription factors are involved in TFH cell differentiation. IL-6 and IL-21 cytokine-mediated STAT signaling pathways, including STAT1 and STAT3, are crucial for inducing Bcl-6 expression and TFH cell differentiation. TFH cells express important surface molecules such as ICOS, PD-1, IL-21, BTLA, SAP and CD40L for mediating the interaction between T and B cells. Recently, two types of microRNA (miRNA) were found to be involved in the regulation of TFH cells. The miR-17-92 cluster induces Bcl-6 and TFH cell differentiation, whereas miR-10a negatively regulates Bcl-6 expression in T cells. In addition, follicular regulatory T (TFR) cells are studied as thymus-derived CXCR5+PD-1+Foxp3+ Treg cells that play a significant role in limiting the GC response. Regulation of TFH cell differentiation and the GC reaction via miRNA and TFR cells could be important regulatory mechanisms for maintaining immune tolerance and preventing autoimmune diseases such as systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA). Here, we review recent studies on the various factors that affect TFH cell differentiation, and the role of TFH cells in autoimmune diseases.