Project description:Regulatory T cells (Treg) are a cornerstone of immune regulation. Recent evidence indicates that human Treg show plasticity in specific settings. A subpopulation of Treg expressing CD161, a marker associated with T helper (Th)17 cells, have T effector -like characteristics and are enriched at sites of autoimmune inflammation. Here we used RNAseq to confirm the effector-like signature of CD161+ Treg and demonstrated a shared transcriptional signature between CD161+ Treg and CD161+ conventional T cells (Tconv). Pathway analysis suggested that CD161+ T cells have a migratory phenotype, expressing high levels of CCR9 and integrin α4β7, markers associated with gut homing. In response to all-trans retinoic acid, CD161+ T cells expressed higher levels of CCR9 and integrin α4β7 than CD161- T cells. Our data suggest that blood CD161+ T cells may have adopted gut homing properties upon retinoic acid exposure. In contrast to their peripheral counterparts, CD161+ T cells from the site of autoimmune arthritis have a diminished gut homing phenotype and blunted response to retinoic acid. In health, the TCRβ repertoires of CD161+ and CD161- T cells showed limited overlap whereas there is clear overlap in T cell clones from synovial fluid of autoimmune arthritis patients. We therefore propose that CD161+ and CD161- T cells are largely distinct populations in the healthy immune system but that the inflamed site creates an environment where CD161 levels in T cells can be altered, potentially contributing to disease pathogenesis.
Project description:Human T-cells that express CXCR5 and/or CCR6 provide help to naive B-cells for IgG production. To understand the molecular pathways that are shared or unique to individual B helper T-cell subsets in human peripheral blood, CD4+IL-7R+CD25-/lo helper T-cells were purified according to the expression of CXCR5, CCR6, CXCR3, CD161 and CCR5 as follows: 1) TFH17(CD161-): CXCR5+CXCR6+CXCR3-CD161- 2) Th17: CXCR5-CCR6+CXCR3-, CD161+ or CCR5+ 3) CCR6”SP”: CXCR5-CCR6+CXCR3-CD161-CCR5- RNA-seq was performed with FACS-purified T-cell subsets from 3 healthy individuals.
Project description:Cross-species transcriptional network analysis defines shared inflammatory responses in murine and human lupus nephritis[Tubulointerstitial]
