ALPHA-LINOLENIC ACID EFFECTS ON HOST T-CELL DEVELOPMENT AND GUT MICROBIOME

Abstract

Diet supplementation of only alpha-linolenic acid (ALA) in mice showed an increased frequency of CD4+CD8a- T cells in the intraepithelial layer (IEL) of the small intestine, as well as the induction of Foxp3+CD4+CD8aa+ T cells from CD4+CD8a- T cells in the mesenteric lymph node (MLN). Attempts to recreate in vivo observations from the MLN in vitro were unsuccessful but suggest the possible expression of G-protein coupled receptor (GPR) 120 and/or GPR40 in CD4+ T cells. Metagenomic analysis of bacterial 16S ribosomal gene in fecal samples showed that bacteria from Lachnospiraceae family may be associated with the increased frequency of CD4+CD8a- T cells in the IEL of the small intestine. With this, specific Lachnospiraceae-derived ALA metabolites may be involved in the expression of CD8aa in CD4+ T cells where it is hypothesized to be orchestrated through GPR signaling. Knowledge here would provide a better understanding on how ALA could alleviate intestinal inflammation.