Table 3.

Studies comparing cTfr and GC Tfr cells

Authors	Gating	Samples	Origin	Phenotype	Function
Sage et al. 16	CD4+ICOS+CXCR5+Foxp3+/GITR+CD19–	Mice immunised with NP‐OVA or NP‐HEL in CFA	Primed by DC, do not require B cells	Memory‐like, persist in vivo for a long time, express similar levels of CXCR5 but lower ICOS, similar proportions in cell cycle	Similar to LN Tfr cells but with a much lower capacity
Dhaeze et al. 15	CD4+CD25+CD127−CXCR5+PD‐1+	Non‐AIDs adult patients with routine tonsillectomies	Lymphoid‐resident Tfr cells after a GC response	Express lower levels of follicular markers (CXCR5, PD‐1, Bcl‐6 and ICOS) but similar levels of regulatory markers (Foxp3 and Helios) with comparable Foxp3 methylation status and higher levels of CD31, CCR7 and CD62L, display a memory phenotype and higher percentage of Th1‐like phenotype	Comparable suppressive function with tonsil‐derived Tfr cells
Fonseca et al. 14	CXCR5+Foxp3+CD4+/CXCR5+CD25+CD127−CD4+	Healthy children with routine tonsillectomies	Peripheral lymphoid tissues before T‐B interaction	Naïve‐like phenotype (high levels of CD45RA, CCR7, CD62L and CD27 and low levels of HLA‐DR), CD45RO−Foxp3lo resting cells are the majority, do not express ICOS, PD‐1 or Bcl‐6	Able to suppress activation of B cells and proliferation of Tfh cells, do not inhibit class switch recombination

AIDs, autoimmune diseases; CFA, complete Freund's adjuvant; cTfr, circulating follicular regulatory T; DC, dendritic cell; GC, germinal centre; HLA‐DR, human leucocyte antigen–DR; LN, lymph node; NP‐HEL, 4‐hydroxy‐3‐nitrophenylacetyl hapten–conjugated hen egg lysozyme; NP‐OVA, 4‐hydroxy‐3‐nitrophenylacetyl hapten–conjugated ovalbumin.