In the colon, NLRP3 inflammasome was activated and its inflammatory cytokines were released in the mice model of GVHD, while berberine could inhibit the NLRP3 inflammasome (Figure 6A–C), TLR4 signalling (Figure 6D) and suppressed inflammatory cytokines except IL‐6 (Figure 6E,F). Here, TLR4 is linked to graft versus host disease.