a, Immunoblot analysis of CASP1 cleavage, total G3BP1 and GAPDH in wild-type and dCas9-expressing immortalized BMDMs transduced with two different gRNAs that target G3bp1. Representative blots (n = 3). b, c, Quantification of inflammatory cytokines in an LPS-induced peritonitis model with or without intraperitoneal injection of arsenite, in serum (b) and in peritoneal fluid (c). P values: **P = 0.0051 (IP-10 in serum), **P = 0.0024 (RANTES in peritoneal fluid) by unpaired two-sided t-test. Data are mean ± s.e.m. (n ≥ 6).