Role of glycolysis in Th17 cell differentiation in autoimmune diseases / 中华微生物学和免疫学杂志

T helper 17 (Th17) cells are closely associated with the pathogenesis of several autoimmune and inflammatory diseases, and selective suppression of Th17 cell production and pathogenicity is an effective strategy for the treatment of these diseases. There is growing evidence that cellular metabolism is associated with the development of autoimmune diseases and determines the differentiation and effector functions of Th17 cells, which undergoes a metabolic reorganization during differentiation from an oxidative phosphorylation-based catabolism to a glucose-based anabolic metabolism in the initial T cells. This paper focused on reviewing recent findings regarding the importance of metabolism in T cell differentiation and autoimmune diseases, especially in Th17 cells, and discussing the regulatory mechanisms of glycolysis in Th17 cell differentiation. This review summarized the regulation of metabolism on T-cell activation and differentiation, revealed metabolic targets with specific regulation on Th17 cells, and provided reference for finding potential therapeutic targets for Th17 cell-mediated autoimmune diseases.

Effects of different immunogenic amino acids in PD-L1 vaccine on the differentiation of T cell subsets / 中国药科大学学报

@#To compare the effects of endogenous 3-nitrotyrosine and non-natural 4-nitrophenylalanine in PD-L1 vaccine on the differentiation of T cell subsets, two immunogenic amino acids were introduced into the same site of PD-L1 vaccine. Two PD-L1 mutants with 3-nitrotyrosine and 4-nitrophenylalanine were obtained, respectively, using genetic code expansion technology. Mice were immunized with these two mutants, and their effects on the differentiation of T cell subsets in spleen were analyzed. The results of flow cytometry showed that the introduction of 4-nitrophenylalanine in PD-L1 vaccine could promote the polarization of Th1 cells while reducing the proportion of Treg cells; the introduction of 3-nitrotyrosine had no effect on the polarization of Th1 cells, while significantly increasing the proportion of Treg and Th17 cells. The introduction of both into PD-L1 vaccine could promote the response of CD8+ T cells in spleen, and the response of PD-L1 mutant containing 4-nitrophenylalanine was stronger. In summary, the non-natural 4-nitrophenylalanine is more suitable for the design of tumor vaccines as compared with endogenous 3-nitrotyrosine.

Deubiquitinases as pivotal regulators of T cell functions / 医学前沿

T cells efficiently respond to foreign antigens to mediate immune responses against infections but are tolerant to self-tissues. Defect in T cell activation is associated with severe immune deficiencies, whereas aberrant T cell activation contributes to the pathogenesis of diverse autoimmune and inflammatory diseases. An emerging mechanism that regulates T cell activation and tolerance is ubiquitination, a reversible process of protein modification that is counter-regulated by ubiquitinating enzymes and deubiquitinases (DUBs). DUBs are isopeptidases that cleave polyubiquitin chains and remove ubiquitin from target proteins, thereby controlling the magnitude and duration of ubiquitin signaling. It is now well recognized that DUBs are crucial regulators of T cell responses and serve as potential therapeutic targets for manipulating immune responses in the treatment of immunological disorders and cancer. This review will discuss the recent progresses regarding the functions of DUBs in T cells.

Research on the mechanism of benzothiazole derivative BD960 on T cell proliferation / 医学研究生学报

Objective Benzothiazole derivative BD960 has immunosuppressive activity after cell -based assays for high-throughput screening.The paper aimed to investigate the involved mechanism of BD960 on T cell proliferation. Methods Human peripheral blood T-lymphocytes were isolated and purified by the immunomagnetic microbeads.Then the T cells were activated by anti-CD3/anti-CD28 mAbs or alloantigen.The effect of BD960 on activa-ted T cell proliferation, the cytotoxic effect BD960 on resting T cells and the expression of activated T cells marker CD25 were measured by flow cytometer.Cytokine levels, including IL-2, IL-4, IL-6, IL-10, IL-17A and IFN-γ, were determined by ELISA. Results BD960 significantly inhibited the proliferation of T cells stimulated by anti-CD3/anti-CD28 mAb or alloantigen in a dose-dependent manner.The IC50 value is (2.3 ±0.3)μmol/L or (2.5 ±0.3)μmol/L, respectively.Moreover, BD960 had no obvious cytotoxic effects on rest-ing T cells and peripheral blood mononuclear cells, even at a high concentration ( up to 100μmol/L) .The ratio of CD25 expression on T cell was 69.7%after stimulated by Anti-CD3/CD28 mAbs with 72 h, the concentration (0.625、2.5、10)μmol/L of BD960 also had no potent effects on the ratio, but 0.1μmol/L FK506 could inhibit CD25 expression as low as 9.4%.The G0/G1 phase of activated T cells was 58.5%after stimulated by BD960 with 96 h.BD960 could induce cell cycle arrest at the G0/G1 phase in activated T cells with the increase of concentration and RAPA in the concentration of 0.1 μmol/L was 91.5%.In addition, BD960 (0.625、2.5、10)μmol/L could inhibit the secretion of IFN-γ, IL-6 and IL-17 in activated T cells with the increase of concentration, without any effects on the secretion of IL-2, IL-4 and IL-10. Conclusion BD960 not only exerts the inhibition on the late stage of T cell activation of cell proliferation but also inhibits the secretion of inflammatory cytokines, such as IL-6, IL-17 and IFN-γ, while the mechanism of BD960 on T cell proliferation was not the same as FK506.As a result, BD960 has the potential to be the lead compound to develop a new immunosuppressant.

Regulation of T cell lineage commitment by SMAR1 during inflammatory & autoimmune diseases.

Background & objectives: CD4+ T cells are involved in abnormal inflammatory responses causing adverse effects to the body. Th17 cells play a major role in immune disorders and the exact mechanism by which CD4+ T cells regulate its effector Th1 and Th17 phenotype at chromatin level is not clearly understood. This study was aimed to understand the role of matrix associated region (MAR) binding protein SMAR1 (scaffold/matrix attachment region binding protein 1) in T cell differentiation during inflammatory and autoimmune condition using SMAR1 transgenic mice as model. Methods: Wild type (C57BL/6J) and SMAR1 transgenic mice were used for isolation of T cells and further identification of different T cell lineages, along with histological analysis. Further, we studied autoimmune and inflammatory diseases using chemically induced and T cell transfer model of colitis and rheumatoid arthritis to better understand the role of SMAR1 in immune responses. Results: SMAR1 transgenic mice were resistant to dextran sodium sulphate (DSS) induced colitis with decreased expression of Th1 and Th17 specific cytokines. Overexpression of SMAR1 repressed Th17 response by negatively regulating RORγt and IL-17 expression. Downregulation of SMAR1 upregulated signal transducer and activator of transcription 3 (pSTAT3) and IL-17 expression that caused generation of more proinflammatory Th1 and Th17 cells leading to inflammation and disease. Interpretation & conclusions: Our results show an important role of SMAR1 in regulating CD4+ T cell differentiation during inflammatory disorders via regulation of both Th1 and Th17 signaling pathways. This study reveals a critical role of SMAR1 in maintaining the proinflammatory immune responses by repressing Th1 and Th17 cell function and it gives the novel insight into immune regulatory mechanisms.

Inhibitory effect of small molecule compound BD691 on activated T cell proliferation and its mechanism / 医学研究生学报

Obej ctive Abnormal proliferation of T cells plays an important role in the development of autoimmune diseases. The article aimed to study the inhibitory effect of small molecule compound BD691 on T cell proliferation and its mechanism. Methods Human peripheral blood T-lymphocytes were isolated and purified by the immunomagnetic microbeads,then T cells were ac-tivated with anti-CD3/CD28 mAbs or alloantigen.The inhibitory effect of BD691 on activated T cell proliferation, the cytotoxic effect BD891 on resting T cells and the expression of activated T cells marker CD25 were measured by flow cytometry.Furthermore, ELISA was used to detect the secretion of cytokines associated with T cell differentiation. Results BD691 significantly inhibited the prolif-eration of T cells being stimulated by anti-CD3/CD28 mAb or alloantigen in a dose-dependent manner, and IC50 values are (8.5 ± 1.5)μmol/L and (7.2 ±1.3)μmol/L, respectively.However, BD691 had no obvious cytotoxic effects on resting T cells and periph-eral blood mononuclear cells, even at a high concentration ( up to 100μmol/L) .In T cells which were not activated by anti-CD3/CD28 mAb, the percentage of CD25+T cells is only 1.6%of the total cells, while the number increased to 68% after activating treatment.Mean-while, in T cells which were activated by 0, 3.3, 10, 30μmol/L BD691, no obvious change of CD25 expression were observed, while immunosuppressant FK506 (0.1μmol/L) significantly decreased the expression of CD25 +T cells (14.9%).In unactivated T cells, 95.6%cells were at G0/G1 phase, while after activation, the percentage of cells at G0/G1 phase reduced to 57.7%.In addition, BD691 inhibited the secretion of IFN-γ, IL-6 and IL-17 in activated T cells, but had no effects on the secretion of IL-2, IL-4 and IL-10. Co nclusion BD691 exerts no effects on T cell activation, but it inhibits T cell proliferation by inducing T cell cycling arrest at G0/G1 phase.Moreover, BD691 inhibits the secretion of key cytokines (such as IFN-γ, IL-6, IL-17) closely related to the differ-entiation of Th1 and Th17 cells.The results suggest that BD 691 is a potential lead compound to develop a new immunosuppressant for the inhibition of abnormal proliferation and differentiation of T cells.