Figure 3

CD23^hiCD58⁺ cells proliferate and constitute the bulk of the population by day 30. A. Carboxyfluorescein diacetate, succinimidyl ester (CFSE)-labeled B cells were exposed to EBV and harvested on day 5. CD58⁺ cells or CD58^- cells were examined for proliferation and intracellular expression of IL6 (using APC-anti-IL6 antibody). Percentages represent fraction of gated cells (CD58⁺ or CD58^-) producing IL6. G0-3 represents non-proliferated cells (G0) and three generations of progeny (G1-3). Percentages above G0-3 indicate the fraction of CD58⁺ or CD58^- cells in each generation. B. EBV-exposed B cells were harvested on days 5, 6 and 7, and examined for expression of CD23 (PE) and CD58 (PE-Cy7). Percentages represent fractions of cells in regions R1 (CD23^loCD58^-), R2 (CD23^loCD58⁺), and R3 (CD23^hiCD58⁺). C. In a separate experiment, EBV-exposed cells (top panels) were harvested on days 4, 5, 6, 7, 10, and 30 and un-infected cells (bottom five panels) were harvested on days 4, 5, 6, 7, and 10 and examined for expression of CD23 and CD58. Percentages of cells in regions R1, R2, and R3 are shown. EBV-exposed cells harvested on day 30 and stained with PE and PE-Cy7 isotype control antibodies are also shown. D. CFSE-labeled B cells were exposed to EBV, harvested on day 5, and examined for expression of CD23 (PE) and CD58 (PE-Cy7). Cells in region R1, R2, and R3 were examined for proliferation and expression of IL6 (APC) by flow cytometry. Percentages represent fraction of cells in regions R1, R2, or R3 that produced IL6. Percentages above G0-3 indicate non-proliferating cells (G0) and proliferating cells (G1-3).