245.12: 4-Octyl Itaconate Inhibits T Cells’ Proliferation and Aerobic Glycolysis to Prevent Immune Over Activation

Introduction: Classically activated Tcells require glycolysis for survival, differentiation, and effector functions, suggesting that targeted metabolism may be a therapeutic target in autoimmune diseases such as GVHD. Tcells play an irreplaceable role in the occurrence and development of aGVHD. 4-OI has anti-inflammatory effects by targeting GAPDH to reduce aerobic glycolysis in macrophages. However the effect of 4-OI on lymphocytes has not been shown. We hypothesized that 4-OI might target GAPDH downregulation aerobic glycolysis of lymphocytes and prevent immune over activation. Method: Cells proliferation was detected by Ki67 and CFSE. The GAPDH activity assay kit was used to detect GAPDH activity. cells metabolism were examined by seahorse. The secretion of cytokines were detected by CBA and flow cytometry. we established an aGVHD model in mice, After 4 weeks, evaluated the severity of GVHD by clinical score and pathology score. BALB/c donor T cells expressing luciferase linked to the β-actin promoter and used BLI to measure the expansion of donor T cells. Results: In vitro experiments, we did not find differences in survival rate of CD4/CD8 Tcells (92±2%) treated with different 4-OI concentrations. GAPDH activity in activated CD4/CD8 Tcells treated with 4-OI was considerably lower compared to activated cells. The proliferation of activated CD4/CD8Tcells increased significantly, whereas 4-OI treatment greatly suppressed proliferation (CD4 60% vs 9%, CD8 78% vs 20%). 4-OI administration greatly lowered glycolysis capacity and MAX ECAR. It suggests that 4-OI can alter CD4/CD8 Tcells’ metabolic patterns. Finally, we discovered that activated cells generate cytokines. Cytokine production decreased considerably in activated CD4/CD8 Tcells treated with 4-OI compared to activated cells.CD4 Tcells (IFN-γ 14% vs 0.4%, TNF 16779pg/ml vs 12095pg/ml, CD107A 56% vs 24%, Granzyme B 26% vs 16%), CD8 Tcells (IFN-γ 13% vs 4%, TNF 2311pg/ml vs 880pg/ml, CD107A 53% vs 16%, Granzyme B 51% vs 28%). In GVHD disease model mice, 4-OI treatment reduced GVHD sign manifestations and clinical scores, and improved survival rates. BLI imaging showed that 4-OI treatment resulted in a significant decrease in proliferation of donor Tcells. In the 4-OI treatment group, the glycolysis rate of Tcells from spleen of recipient mice was significantly decreased. And when we detected the cytokines of the serum, the levels of TNF-α, IFN-γ, IL-10, MCP-1, IL-12p70 and IL-6 from 4-OI treatment group were also greatly reduced compared to the control group. Conclusion: In this study, we demonstrated that 4-OI did not affect the viability of rest T cells however it could inhibit the proliferation and function of activated T cells by decreasing aerobic glycolysis which suggested 4-OI a potential therapeutic agent in GVHD and autoimmune diseases. Natural Science Foundation of Hunan Province, China (Grant No.:2021JJ31018).