NOS2 and Granuloma: M1 polarization of microglia/macrophages existed in S. japonicum egg-induced granulomas only on day 3 post injection (Fig. 7a) and specific marker iNOS staining was negative after that (Fig. 7b-d), while M2 polarization sustained from day 3 until inflammation subsidence on day 30, as indicated by positive expression of both Arg1 (red) and IBA1 (green), colocalization of which confirmed M2 microglia/macrophages in the vicinity of the eggs (Fig. 7e-m).