No influence of FTY720 treatment on peritoneal B1 B-cell progenitor. (A) B1 B-cell progenitors were determined as CD11b⁻CD11c⁻IgM⁻B220^int-negCD19⁺ cells. These cells were isolated from the PerC 6 hours after mock (top panels) or FTY720 (bottom panels) treatment. Data are representative of 3 independent experiments. (B) The number of peritoneal CD11b⁻CD11c⁻ IgM⁻B220^int-negCD19⁺ cells was calculated by using the total cell number and the flow cytometric data. Horizontal bars represent the mean.