Autocrine secretion of IL-10 and expression of IL-10 receptors on DLBCL cells. (A) IL-10 mRNA in DLBCL lines was detected by RT-PCR. (B) Cell-culture supernatants were collected from various DLBCL cell lines and subjected to IL-10 ELISA. Data represent means ± SD of 3 independent experiments. (C) Surface IL-10 receptors were analyzed in DLBCL patient cells (top panel) and DLBCL cell lines (bottom panel) by flow cytometry. (D) DHL2 and Ly3 cell lines were treated with a 4μM concentration of the JAK2 inhibitor TG for various times and the supernatants were collected and subjected to IL-10 ELISA. Means ± SD from 4 determinations obtained in 2 separate experiments are shown.