Figure 2.

Effects of various inhibitors on MERTK-mediated efferocytosis and cell growth. A, effect of various inhibitors on efferocytosis by rpMacs. Resident peritoneal cells were pretreated with the indicated concentration of each inhibitor and subjected to an efferocytosis assay with pHrodo-labeled apoptotic thymocytes in the presence of the inhibitor. Efferocytosis (the percentage of pHrodo-positive cells) was determined by flow cytometry and is expressed relative to that observed without inhibitors. The experiment was done in triplicate, and the average values are plotted with S.D. (error bars). The values were statistically analyzed by Student's t test against the value without inhibitor. ##, p < 0.001. B, effect of various inhibitors on apoptotic cell–promoted cell proliferation. Apoptotic thymocytes were added to Ba/F3 cells expressing WT MERTK and TIM4, and the mixture was incubated in the presence of the indicated concentrations of the inhibitor. After incubation for 24 h, viable Ba/F3 cells were counted. The experiments were carried out three times, and the average values were plotted with S.D. (error bars). Student's t test against the value without inhibitor. The cell number is expressed relative to that observed in the presence of apoptotic cells without inhibitors. The cell number in the absence of inhibitors was 3–5 × 10⁵ cells/ml. #, p < 0.01; ##, p < 0.001; Student's t test.