STAT6 phosphorylation in PMBL-derived cell lines. (A) Cell lysates were prepared from one Burkitt lymphoma-derived cell line (a: Ramos), 2 PMBL-derived cell lines (b: MedB1 and c: Karpas 1106), 4 DLBCL-derived cell lines (d: SUDHL4, e: SUDHL6, f: OCI-Ly3, and g: OCI-Ly10), and 1 Hodgkin-derived cell line (h: L428). Equal amounts of whole cell lysate were subjected to SDS-PAGE followed by Western blot analysis. Phosphorylated STAT6 was identified using phosphospecific antibody for Tyr641 phosphorylated STAT6. Blots were stripped and reprobed with an anti-STAT6 antibody. As a loading control, blots were probed with anti-β-actin antibody. (B) Ramos and MedB1 cells were treated for 10 minutes with 10 ng/mL IL-4 or 5 ng/mL IL-13, or left untreated (-) and samples prepared and analyzed as in panel A.