Effect of interleukin-6 (IL-6) on the porin-induced immunoglobulin G2a (IgG2a) and immunoglobulin A (IgA) expression on B-2 cells. (a) Peritoneal cavity B-2 cells were cultured for 72 hr with complete medium alone (shaded), porin (thick grey line), IL-6 (thin black line) or porin plus IL-6 (thick black line), and analysed by flow cytometry for the expression of IgG2a. (b) Peritoneal cavity B-2 cells were cultured for 72 hr with complete medium alone (shaded), porin (thick grey line), IL-6 (thin black line) or porin plus IL-6 (thick black line), and analysed by flow cytometry for the expression of IgA. Data shown are representative of three independent experiments.