Cat S is essential for macrophage autophagy contributing to M2-type polarization of macrophages. WT or Cat S-/- macrophages were pretreated with 50 μmol/L autophagy inhibitor (Chloroquine, CQ) or DMSO (vehicle) for 1 hr and then subjected to SL4 cells coculture, serum-starved for at least 12 hrs before co-culture. Quantitative real-time PCR analysis of the mRNA expression of M2 marker (Arg-1, FIZZ1, IL-10) or M1 marker (iNOS, IL-1β, TNF-α). Tubulin was a normalization control. Data are mean ± SEM of 3 independent experiments. *, P<0.05. **, P<0.01. NS indicates not significant. Mφ indicates macrophages.