KO Vdr -/- mice; Bone marrow derived macrophages (BMDMs); Briefly, femora and tibia of the hind legs were flushed with cold DMEM (Invitrogen) containing 10 % heat-inactivated fetal calf serum (Biowest), 200 mM L-glutamine, and penicillin/streptomycin (Invitrogen). This complete medium was supplemented with M-CSF (50 ng/ml) and bone marrow cells were cultured at 37°C in a humidified 5% CO2 atmosphere for 7 days. Thioglycolate-elicited macrophages were obtained 4 days after the intraperitoneal injection of sterile 4 % thioglycolate medium. Cells were harvested by peritoneal lavage with cold PBS, 1% FCS and were cultured in RPMI 1640 (Invitrogen) including 10 % heat-inactivated fetal calf serum, L-glutamine, and penicillin/streptomycin (P/S). Macrophages were plated at 8 x 104/well in 96-well plates and cultured in P/S-free medium in the presence or absence of IFN-gamma, 1alpha,25(OH)2D3, or both for 24-48 hours.
