Low-dose IL-2 effects on innate lymphoid cells in innate immune-mediated colitis 3041

Abstract Description Interleukin 2 (IL2) in low doses (Ld-IL2) has been approved as a therapy for inflammatory diseases such as arthritis, but the benefits of Ld-IL2 therapy in colitis remains largely unknown. Canonically thought of as a cytokine for T-cell proliferation and regulatory T-cell survival, IL2 is pleiotropic in nature and may also activate anti-inflammatory effects in innate immune cells. villin-A20+/0 x RAG1-/- (TRAG) mice develop early-onset colitis in the absence of adaptive immunity. To assess the effect of Ld-IL2 on innate colitis, we injected TRAG mice with Ld-IL2. Flow cytometry analysis of colonic lamina propria lymphocytes (LPLs) revealed an increase in innate lymphoid cell type 3 (ILC3s), ILC2s, and eosinophils, and a decrease in inflammatory monocytes in TRAG mice treated with Ld-IL2. Histologic signs of colitis were ameliorated in TRAG mice treated with Ld-IL2. Furthermore, ex vivo stimulation with Ld-IL2 induced proliferation/survival of ILC3s from LPLs of TRAG mice colons. This suggests that low-dose IL-2 treatment may help in alleviating colitis through activating ILC3s to produce anti-inflammatory cytokines. Funding Sources NIDDK-DK120320 Topic Categories Mucosal and Regional Immunology (MUC)