RTX did not alter Treg or Tfr numbers within the lymph node. (A) Flow cytometric contour plots, (B) quantitation of the proportion, and (C) total number of FOXP3+CD127−CD4+ Treg from iliac lymph nodes taken prior to kidney transplantation in RTX-treated patients and controls. (D) Contour plots, (E) proportion, and (F) total number of CXCR5+CD57+FOXP3+CD127−CD4+ Tfr from iliac lymph nodes. In graphs, one symbol represents one individual, and the height of the bar represents the mean. (G) IgA production in CD19+CD27+IgD− B cells cultured alone, coculture of B cells with CXCR5+CD57+CD25−CD4+ Tfh cells, or coculture of B cells with Tfh and CXCR5+CD57+CD127−CD25+CD4+ Tfr flow-sorted from iliac lymph nodes. Data in (G) are a representative biological replicate of 3 independent biological replicates. The height of the bars represent the mean of 4 technical replicates, and the error bars show the standard deviation. n.d., not detected above background.