There was a significant elevation in the levels of NLRP3, caspase-1, IL-1β, pNF-κB and pIKKB in PBMCs of IgG4-RD patients (Fig. 4I, J) and Usp25 KO (Fig. S8A), while the expression of TRAF6 was decreased. Here, CASP1 is linked to immunoglobulin G4-related sclerosing disease.