Repression of miR-31 by BCL6 stabilizes the helper function of human follicular helper T cells

Abstract

Significance Antibody production by B lymphocytes generally requires help by T follicular helper (T FH ) cells, a specific subset of CD4 + T lymphocytes. The function of T FH cells depends on BCL6, a transcriptional repressor whose target genes that account for the helper activity are unknown. By the combined analysis of microRNA (miRNA) and gene expression profiling in human T FH cells, we found that miR-31, a miRNA that inhibits gene transcripts relevant for T FH cells biology, is down-regulated in T FH . BCL6 contributes to “helperness” by shutting down miR-31 gene expression, thus stabilizing the follicular helper T cell program. Thus miR-31 is a therapeutic target to modulate human T cell-dependent antibody responses in immunomediated disorders.