IL-10-producing B cell frequency is elevated in PBMC of untreated HIV-1 infection.

<p>(A) Gating strategy for identification of <i>ex vivo</i> IL-10-producing B cells in PBMC. (B) Flow cytometry dot plots of IL-10-producing B cells in unstimulated PBMC and PMA/ionomycin-stimulated PBMC from representative HIV-1 infected individuals and a healthy donor. (C) Summary data of IL-10-producing B cell frequencies in unstimulated PBMC from a cohort of HIV-1 infected individuals at different stages, healthy donors, and HCV mono-infected individuals. Each circle represents one individual. (D) IL-10 production from purified B cells of healthy donors and untreated HIV-1 infected individuals. B cells were purified from PBMC and cultured in unstimulated medium for 12 h and then IL-10 in the supernatant was measured by a Luminex assay. (E) Summary data showing IL-10-producing B cell frequency in PBMC stimulated 5 h with PMA/ionomycin from healthy donors and HIV-1 infected individuals. HIV-1 neg: healthy donors. CI: untreated chronic HIV-1 infection. TCI: treated chronic HIV-1 infection. EI: untreated early HIV-1 infection. LTNP: long-term non-progressors. HCV: HCV mono-infection. Isotype: representative IL-10 antibody isotype control from the same EI patient shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0089236#pone-0089236-g001" target="_blank">Figure 1B</a>. *: <i>P</i><0.05. **: <i>P</i><0.01. ***: <i>P</i><0.001. N.S.: non-significant (Kruskal-Wallis one-way ANOVA and Dunn’s test). For flow cytometry analysis, >1.5 million events in the lymphocyte gate were collected.