Cellular composition of tumor lymph nodes from Roquin^san/+ mice. Frequency of cellular subsets as measured by flow cytometry. (A) Lymphocyte composition of tumor (Tm) and nontumor (nTm) lymph nodes from Roquin^san/+ and Roquin^+/+mice. (B-C) Percentage of T_FH (CD4⁺PD-1^hiCXCR5⁺) and GC B (B220⁺FAS⁺GL7^hi) cells in enlarged (tumor) and nonenlarged (normal) lymph nodes from Roquin^san/+ mice compared with control Roquin^san/+ and Roquin^+/+mice. (D) Representative FACS plots showing the percentage of T_FH based on CD4⁺PD-1^hiBcl-6⁺ cells in tumor, nontumor lymph nodes compared with normal Roquin^san/+ mice. (E-F) Comparison of T_FH cells (CD4⁺PD-1^hiBcl-6⁺), frequency (as %CD4⁺), and total numbers in tumor and contralateral nontumor lymph nodes compared with lymph nodes from normal Roquin^san/+ mice. (G-H) Proportions of T_FH (G) and GC B cells (H) undergoing proliferation, as indicated by expression of Ki-67. Histograms in all panels show the mean with SEM (A) or median (B-H) values of 2 to 10 mice 26 to 40 weeks of age. Results are representative of at least 2 independent experiments. ns indicates not significant. *P < .05; **P < .01; ***P < .001.