Integrative transcriptomic analysis identifies TAZ as a conserved candidate associated with intestinal Th17/Treg imbalance in type 2 diabetes

Abstract Background Intestinal Th17/Treg immune imbalance contributes to type 2 diabetes mellitus (T2DM), but their key molecular regulators remain unclear. Methods Single-cell and bulk transcriptomic datasets from control diet- and high-fat diet-fed mice were integrated using differential expression, functional enrichment, co-expression network, cell communication, virtual knockout, and machine-learning analyses. Candidate genes were validated in an independent dataset and in colonic tissues from diabetic KKAy and control C57BL/6J mice, and Th17/Treg populations were assessed by flow cytometry. Results High-fat diet altered colonic immune composition and pathways related to T-cell differentiation, inflammation, and metabolism. TAZ was the only gene shared between Th17/Treg-associated genes and differentially expressed genes across three datasets, with its differential expression confirmed in an independent dataset. Virtual TAZ knockout perturbed pathways involving tight junctions, T-cell receptor signaling, and cell adhesion. T-cell co-expression modules and machine-learning-selected genes were enriched in TGF-β signaling and Th17/Treg differentiation. Diabetic KKAy mice showed increased colonic TAZ, RORγt, IL-17 A, IL-23, and pro-inflammatory cytokines, together with reduced FOXP3 and TGF-β expression. Flow cytometry further confirmed increased Th17 and reduced Treg cells in KKAy mice. Conclusion TAZ is a conserved candidate associated with intestinal Th17/Treg imbalance and inflammation in T2DM. Although in silico knockout predicted pathway perturbations, its causal role remains to be experimentally established.