Mutual modulation of gut microbiota and the immune system in type 1 diabetes models

Abstract

Immunological disorders; Metabolic disorders; Molecular biology

Trastorns immunològics; Trastorns metabòlics; Biologia molecular

Trastornos inmunológicos; Trastornos metabólicos; Biología Molecular

The transgenic 116C-NOD mouse strain exhibits a prevalent Th17 phenotype, and reduced type 1 diabetes (T1D) compared to non-obese diabetic (NOD) mice. A cohousing experiment between both models revealed lower T1D incidence in NOD mice cohoused with 116C-NOD, associated with gut microbiota changes, reduced intestinal permeability, shifts in T and B cell subsets, and a transition from Th1 to Th17 responses. Distinct gut bacterial signatures were linked to T1D in each group. Using a RAG-2−/− genetic background, we found that T cell alterations promoted segmented filamentous bacteria proliferation in young NOD and 116C-NOD, as well as in immunodeficient NOD.RAG-2−/− and 116C-NOD.RAG-2−/− mice across all ages. Bifidobacterium colonization depended on lymphocytes and thrived in a non-diabetogenic environment. Additionally, 116C-NOD B cells in 116C-NOD.RAG-2−/− mice enriched the gut microbiota in Adlercreutzia and reduced intestinal permeability. Collectively, these results indicate reciprocal modulation between gut microbiota and the immune system in rodent T1D models.

This work was supported by the Plan Nacional de I + D + i of the Spanish Ministry of Science and Innovation (PID2019-109302RB-I00), the DiabetesCERO Foundation (Becas Impulso Talento Joven 2022), and CIBER of Diabetes and Associated Metabolic Diseases (CIBERDEM) that is an initiative from Instituto de Salud Carlos III (Spain). E.R.-M. was supported by predoctoral fellowships from the Generalitat de Catalunya (AGAUR FI-DGR, grant number: 2013FI_B 00585), the Spanish Government (FPU, grant number: FPU13/02045) and the IRBLleida. M.C.-P., B.A., and L.E.-M. were supported by UdL and IRBLleida predoctoral fellowships. F. Y. was supported by a predoctoral fellowship from the Chilean Government (ANID, grant number: 72190278). G.S.-G. was supported by a predoctoral fellowship from VHIR.