BAFF and APRIL rescue myeloma cells from dexamethasone-induced apoptosis. (A) RPMI 8226 and L363 myeloma cells were cultured in the presence of DEX (10^-6 M) with or without IL-6 (3 ng/mL), BAFF (200 ng/mL), or APRIL (200 ng/mL). Cells were recovered after 3 days of culture and apoptotic cells were detected by annexin V staining. Results are those of one experiment of 5. The percentage of apoptotic cells is indicated in each panel. (B) Mononuclear cells from 8 patients with MM were cultured for 4 days in the presence of IL-6 (1 ng/mL) with or without DEX (10^-6 M), BAFF (200 ng/mL), or APRIL (200 ng/mL). At day 4 of culture, the viability and total cell counts were assessed and the percentage of CD138⁺ viable plasma cells was determined by flow cytometry. Results are median values of the numbers of myeloma cells in the culture wells. The values were compared with a Wilcoxon test for pairs.