Fig. 2
Costimulation with γ-IFN completely blocks the LPS-induced release of MIP-1α by murine thioglycollate-elicited peritoneal exudate macrophages in vitro, while sparing the MIP-1β response. (A) Macrophages (1 × 106 cells) were incubated for 18 hr in medium supplemented with the indicated amount of LPS, either in the absence (solid bars) or presence (cross-hatched bars) of γ-IFN (200 units/ml). Culture medium was then removed and the MIP-1α content quantified by specific ELISA. Data are from a representative experiment (of 3) and are expressed as the mean ± SD of values obtained from duplicate macrophage stimulations. The % values noted above each cross-hatched bar refers to % suppression in γ-IFN-treated cultures compared with control cultures in which γ-IFN was not included. (B) As in (A), macrophages (1 × 106 cells) were incubated for 18 hr with the indicated amount of LPS either in the absence (solid bars) or presence (cross-hatched bars) of γ-IFN (200 units/ml). Culture medium was then removed and the MIP-1β content quantified by specific sandwich ELISA. Data are from a representative experiment and are expressed as the mean ± SD.