Transcriptional profiling of IL-10 producing vs non producing human TFR2 cells

Background information: Antibody responses to most infectious and food protein antigens depend on help to B cells from specialised T follicular helper (Tfh) cells. A subset of Foxp3+ regulatory T cells (Tregs) has been described in mice, with a prominent role in repressing germinal center reactions that are critical for memory B cell formation and long-lived antibody responses. These specialised Tregs co-opt the Bcl-6-dependent Tfh differentiation pathway in order to access the B cell-rich follicles and have therefore been designated as T follicular regulatory (Tfr) cells. Preliminary results: We identified a unique Bcl-6-expressing follicular regulatory T cell in human secondary lymphoid tissue, designated hereafter as Tfr2 cells, that lacks Foxp3 expression and the thymic-imprinted Foxp3 methylation pattern, but shares expression of key Treg molecules. Interestingly, 25% of these cells are the predominant source of T cell-derived IL-10 in human tonsil, an important cytokine with immunomodulatory properties. Aims of this study: We performed transcriptional profiling using affymetrix microarrays to interrogate wether IL-10 producing vs non producing human Tfr2 cells were fundamentally different subsets. 2 cell types (IL-10+ vs IL10- TFR2 cell subsets) obtained from 3 different tonsil donors (biological replicates)