Cytokine expression by fresh T and MM cells. Fresh T cells purified from PBMCs of patients with MM with or without osteolysis as well as from controls were analyzed for RANKL, OPG, and TRAIL expression, respectively, by RT-PCR (A) and Western blotting (B). MM cells purified from BM of patients with MM with osteolysis were analyzed for RANKL expression by RT-PCR (C). The results show the overexpression of RANKL, OPG, and TRAIL by fresh T cells from patients with MM with osteolysis compared with those without osteolysis and controls (A-B). MM cells were found not expressing RANKL (C). The intensity of the bands obtained by RT-PCR was quantified by densitometry (histograms) and normalized to GAPDH.