The identification that T follicular helper (Tfh) cells is critical for the emergence of germinal centre responses prompted the study of CXCR5-expressing CD4+ T cell subsets in autoimmunity. However, circulating CXCR5-expressing T cells are heterogeneous by containing Forkhead box protein 3 (FoxP3)+ T follicular regulatory (Tfr) cells in addition to bona fide Tfh cells. Such heterogeneity may hamper the analysis of the contribution of specific follicular T cell subsets for autoimmune pathogenesis. Therefore, separate assessment of Tfh and Tfr populations offer greater opportunities for stratification of autoimmune patients, such as Sjögren's syndrome patients.
Keywords: Foxp3; Sjögren’s syndrome; T follicular helper cells; T follicular regulatory cells.
© 2019 British Society for Immunology.