Pathologically expanded peripheral T helper cell subset drives B cells in rheumatoid arthritis
Research output: Contribution to journal › Article › peer-review
Colleges, School and Institutes
- Harvard Medical School
CD4+ T cells are central mediators of autoimmune pathology; however, defining their key effector functions in specific autoimmune diseases remains challenging. Pathogenic CD4+T cells within affected tissues may be identified by expression of markers of recent activation1. Here we use mass cytometry to analyse activated T cells in joint tissue from patients with rheumatoid arthritis, a chronic immune-mediated arthritis that affects up to 1% of the population2. This approach revealed a markedly expanded population of PD-1hiCXCR5−CD4+ T cells in synovium of patients with rheumatoid arthritis. However, these cells are not exhausted, despite high PD-1 expression. Rather, using multidimensional cytometry, transcriptomics, and functional assays, we define a population of PD-1hiCXCR5− ‘peripheral helper’ T (TPH) cells that express factors enabling B-cell help, including IL-21, CXCL13, ICOS, and MAF. Like PD-1hiCXCR5+ T follicular helper cells, TPHcells induce plasma cell differentiation in vitro through IL-21 secretion and SLAMF5 interaction (refs 3, 4). However, global transcriptomics highlight differences between TPHcells and T follicular helper cells, including altered expression of BCL6 and BLIMP1 and unique expression of chemokine receptors that direct migration to inflamed sites, such as CCR2, CX3CR1, and CCR5, in TPH cells. TPH cells appear to be uniquely poised to promote B-cell responses and antibody production within pathologically inflamed non-lymphoid tissues.
|Early online date||1 Feb 2017|
|Publication status||Published - 2 Feb 2017|
- PD-1, mass cytometry, follicular helper T cells, rheumatoid arthritis, plasma cells, CCR2, autoimmunity , antibodies , follicular T-helper cells , translational immunology