Downregulation of chemokine receptor 9 facilitates CD4⁺CD8αα⁺ intraepithelial lymphocyte development.

ABSTRACT: Intestinal intraepithelial lymphocytes (IELs) reside in the gut epithelial layer, where they help in maintaining intestinal homeostasis. Peripheral CD4⁺ T cells can develop into CD4⁺CD8αα⁺ IELs upon arrival at the gut epithelium via the lamina propria (LP). Although this specific differentiation of T cells is well established, the mechanisms preventing it from occurring in the LP remain unclear. Here, we show that chemokine receptor 9 (CCR9) expression is low in epithelial CD4⁺CD8αα⁺ IELs, but CCR9 deficiency results in CD4⁺CD8αα⁺ over-differentiation in both the epithelium and the LP. Single-cell RNA sequencing shows an enriched precursor cell cluster for CD4⁺CD8αα⁺ IELs in Ccr9^-/-

SUBMITTER: Ono K 

PROVIDER: S-EPMC10449822 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature