Fluoxetine actions on and Bcl-2 levels in normal B cells and non-BL cell lines.

(A) Resting tonsilar B cells were cultured at 10⁵ cells per 200 μL culture medium for 48 hours in flat-bottom microtiter wells with either no addition (CM), Staphylococcus aureus Cowan 1 (SAC, 1:10 000), phorbol 12-myristate 13-acetate (PMA, 5 ng/mL), SAC+sCD40L (1μg/mL), or PMA + ionomycin (PMA/I, 1 μg/mL), before addition of fluoxetine at 0 to 20 μM as indicated. Cells were then cultured for a further 24 hours, pulsed with ³[H]-thymidine for the last 7 hours for the analysis of DNA synthesis. (B) Cells from lines indicated were cultured for 24 hours with fluoxetine as in panel A before assessment of DNA synthesis as described in Figure 1A-D. Data are means ± SEMs from 3 separate experiments. (C-D) Cell lysates were prepared from pelleted cells and equal amounts of protein (25 μg) resolved on 12.5% SDS-PAGE before blotting for Bcl-2, the protein migrating with an apparent molecular weight of 26 kDa as indicated. Panel C is a representative blot of protein from L3055 (wild type), L3055 vector controls, L3055/Bcl-2 transfectants, Namalwa, Elijah, Mutu I, and resting tonsilar B cells; panel D, from Nalm 6, CEM, Jurkat, J10, RPMI8226, resting tonsilar B cells, and B cells activated for 48 hours with PMA+ionomycin.