BCL6 and nasal cavity polyp: CXCR5+ Bcl6+ Tfh cells are enriched in the lymphoid aggregates that form in these polyps compared to healthy tissue; however, Bcl6 expression is relatively infrequent in nasal polyps overall (perhaps 2–5% of CD4+ T cells), with higher frequencies in T cells from polyps that contained GCs or eosinophils [68–70].