Expression of IL-6 and its receptors by MCL. ELISA detected the levels of (A) IL-6 or (B) gp80 in culture media of MCL cell lines and primary MCL cells from 7 patients (PT1-PT7), (C) IL-6, and (D) gp80 in culture media of MCL cells after serum starvation or treatment with a low dose (2nM) of BTZ for 12 hours, and (E) IL-6 and gp80 in culture media of PBMCs from 4 blood donors (PBMC1-PBMC4). Also shown is flow cytometry analysis for the expression of gp130 on (F) MCL cell lines and (G) primary MCL cells from 4 patients (PT1-PT4).