Adoptive transfer of ionomycin-treated Trpm2^−/− peritoneal macrophages ameliorated Escherichia coli sepsis in Trpm2^−/− mice. Trpm2^−/− peritoneal macrophages were treated with 2 µM ionomycin or vehicle control dimethyl sulfoxide (DMSO) for 5 min and then injected into the peritoneal cavity of Trpm2^−/− mice (5 × 10⁵ cells per mice) 2 h before intraperitoneal challenge of E. coli. (A) The 72-h survival rates were assessed (n = 21 per group). Kaplan–Meier log-rank test. (B) Bacterial burdens in the peritoneal cavity were determined 12 h after injection of E. coli (n = 7 per group). Student’s t test. *P < 0.05; **P < 0.01. CFU = colony-forming units; PLF = peritoneal lavage fluid; TRPM2 = transient receptor potential melastatin 2.