PT  - JOURNAL ARTICLE
AU  - Pineda, Miguel
AU  - Pan, Piaopiao
AU  - Wang, Yilin
AU  - Khan, Aneesah
AU  - Nyirenda, Mukanthu H.
TI  - CD20<sup>+</sup> T cells are associated with inflammatory responses in experimental arthritis
AID  - 10.1101/2021.10.12.464081
DP  - 2021 Jan 01
TA  - bioRxiv
PG  - 2021.10.12.464081
4099  - http://biorxiv.org/content/early/2021/10/12/2021.10.12.464081.short
4100  - http://biorxiv.org/content/early/2021/10/12/2021.10.12.464081.full
AB  - CD20+ T cells comprise a small but highly inflammatory subset that has been implicated in autoimmunity, including rheumatoid arthritis (RA). We sought to characterise the CD20+ T cell subset at the site of inflammation in murine collagen-induced arthritis (CIA) model of RA and investigate the phenotype and functional relevance of CD3+CD20+ T cells in the lymph nodes and arthritic joints using flow cytometry and immunohistochemistry. We demonstrate that CD3+CD4+CD20+ and CD3+CD8+CD20+ T cells are expanded in the draining lymph nodes of CIA mice. In addition, compared to naïve mice and those that did not develop clinical symptoms, CD20 expressing T cells of arthritic mice produced increased levels of pro-inflammatory cytokines (GM-CSF, TNF-a, IL-17, and INF-g). Notably, CD3+CD4+CD20+ and CD3+CD8+CD20+ T cells of disease mice were enriched with CXCR5+PD-1+ T follicular helper cells and CXCR5-PD-1+ peripheral T helper cells, subsets of T cells that have been implicated in promoting B-cell responses and antibody production within pathologically inflamed non-lymphoid tissues in RA. Importantly, CD3+CD20+ T cells were detected in the inflamed regions in the lymph nodes and paws of arthritic mice. Our findings suggest that CD20+ T cells are associated with inflammatory responses in the arthritic joint and may exacerbate pathology by promoting inflammatory B cell responses.Competing Interest StatementThe authors have declared no competing interest.