Figure 2. OS induced M2-TAM activation and boosted exosome-derived miR-221-3p. M2-TAMs were co-cultured with 143B and Saos2 cells. (A–D) qRT-PCR assayed the contents of macrophage polarization markers IL-1β, IL-10, Arg1 and YM1; (E) The iNOS and STAT6 profiles were verified by WB; (F) qRT-PCR was utilized to test the miR-221-3p level. **P < 0.01, ***P < 0.001 (VS con group), N = 3.