Expression and production of cytokines by DC progenitor cells from healthy donors (HD) and myeloma patients (MM). (A) RT-PCR detecting mRNA expression for IL-6, IL-10, and TGF-β1 in freshly isolated monocytes (day 0) and day-2–cultured cells from a healthy donor and a myeloma patient. Representative results of 4 independent experiments are shown. ELISA detecting (B) IL-6 or (C) TGF-β1 in the supernatants of day-3 cultures of the cells. Shown are the mean ± SD of the results obtained from all tested healthy donors (n = 7 for IL-6, and n = 3 for TGF-β1) and myeloma patients (n = 7 for IL-6, and n = 3 for TGF-β1). ** P values less than .01.