Indirubin regulates T cell differentiation by promoting αVß8 expression in bone marrow-derived dendritic cells to alleviate inflammatory bowel disease.

Inflammatory bowel disease is a disease that can invade the whole digestive tract and is accompanied by immune abnormalities. Immune dysfunction involving dendritic cells (DCs) and T cells is recognized as a key factor in diseases. Indirubin (IDRB) exerts antiinflammatory effects and can help in treating immune diseases. This study aimed to isolate bone marrow-derived dendritic cells (BMDCs) using lipopolysaccharide (LPS) to obtain mature DCs (mDCs). The expression of CD80, CD86, CD40, and MHC-II was detected using flow cytometry after treatment with IDRB. αVß8 siRNA was used to knock down αVß8 in mDCs, and the expression of CD80, CD86, CD40, and MHC-II was detected. Meanwhile, DCs were co-cultured with T cells. Then, T cell differentiation was detected using flow cytometry, and the cytokine levels were detected using enzyme-linked immunosorbent assay. The animal model of dextran sulfate sodium (DSS)-induced inflammatory bowel disease was established in mice. After intervention with IDRB and αVß8 shRNA, the intestinal tissues were evaluated using H&E staining, disease activity index (DAI) score, and histological damage index, and the corresponding factors and cytokines to regulatory T cells (Treg) and Th17 were measured. The results showed that αVß8 was expressed in immature DCs and mDCs. CD80, CD86, CD40, and MHC-II expression decreased after IDRB treatment in mDCs. Meanwhile, the expression of TNF-α and TGF-ß also decreased after IDRB treatment. The effect of IDRB on the expression of CD80, CD86, CD40, MHC-II, TNF-α, and TGF-ß in mDCs was reversed by αVß8 siRNA. The Treg differentiation increased after IDRB treatment, while the differentiation of Th17 cells was inhibited. This effect of IDRB was reversed by mDCs after treatment with αVß8 siRNA. In vivo experiments showed that IDRB alleviated the symptoms of inflammatory bowel disease in animals. Enteritis significantly reduced, and the effect of IDRB was reversed by αVß8 shRNA. The results suggested that IDRB regulated the differentiation of T cells by mediating the maturation of BMDCs through αVß8. This study confirmed the therapeutic effect of IDRB in inflammatory bowel disease and suggested that IDRB might serve as a potential drug.

Radiosensitivity enhancement by arsenic trioxide in conjunction with hyperthermia in the EC-1 esophageal carcinoma cell line.

OBJECTIVE: To explore the effect on radiosensitivity of arsenic trioxide (As203) in conjunction with hyperthermia on the esophageal carcinoma EC-1 cell line. METHOD: Inhibition of EC-1 cell proliferation at different concentrations of As203 was assessed using the methyl thiazolyl blue colorimetric method (MTT method), with calculation of IC50 value and choice of 20% of the IC50 as the experimental drug concentration. Blank control, As203, hyperthermia, radiotherapy group, As203 + hyperthermia, As203 + radiotherapy, hyperthermia + radiotherapy and As203 + hyperthermia + radiotherapy groups were established, and the cell survival fraction (SF) was calculated from flat panel colony forming analysis, and fitted by the 'multitarget click mathematical model'. Flow cytometry (FCM) was used to detect changes in cell apoptosis and the cell cycle. RESULTS: As203 exerted inhibitory effects on proliferation of esophageal carcinoma EC-1 cells, with an IC50 of 18.7 µmol/L. After joint therapy of As203 + hyperthermia + radiotherapy, the results of FCM showed that cells could be arrested in the G2/M phase, and as the ratio of cells in G0/G1 and S phases decreased, cell death became more pronounced. CONCLUSION: As203 and hyperthermia exert radiosensitivity effects on esophageal carcinoma EC-1 cells, with synergy in combination. Mechanistically, As203 and hyperthermia mainly influence the cell cycle distribution of EC-1 esophageal carcinoma cells, decreasing the repair of sublethal damage and inducing apoptosis, thereby enhancing the killing effects of radioactive rays.