Functional characterization of CD8_CXCR5+ICOS+T cells. (A-B) Cells isolated from lymphoma tissues were stimulated by phorbol 12-myristate 13-acetate/iono in presence of the protein transport inhibitor Golgi Stop. Intracellular cytokine secretion was analyzed in each T-cell subset (n = 4-6). (C) CXCL13 secretion measured by Luminex in the supernatant of each sorted T-cell subset after coculture with autologous B cells in presence of PHA for 48 hours (n = 4). (D) Representative dot plots and histograms for survival (top) and proliferative capacity (bottom) of each T-cell subset after coculture with autologous B cells for 5 days in presence of PHA (results from 3 independent experiments). Survival and proliferation were evaluated by the percentage of lived/dead-negative cells and division index (DI), respectively. The Mann-Whitney nonparametric U test (*P < .05; **P < .01) was performed.