As a classical signaling pathway, P38 MAPK can promote macrophages to secrete inflammatory cytokines such as IL-1β and IL-6, regulate fibrotic factors such as TGF-β and FN1, ultimately induce peritoneal inflammation and peritoneal thickening in a variety of PD-induced PF models [67,68]. The gene discussed is IL6; the disease is pemphigus foliaceus.