BCL-XL inhibitor kills neutrophils elicited during MSU-induced peritonitis in a mouse model of gout. (A) B6 mice were injected with 1 mg MSU crystals IP or left untreated (PBS). Blood (B) and peritoneal cavity (PC) neutrophils were sorted by flow cytometry 16 hours later, and western blot analysis performed to determine the amount of BCL-XL and actin protein. BCL-XL expression is shown relative to actin loading control. A line connects data from each separate experiment. (B-C) B6 mice were injected with MSU crystals IP or left untreated. Four hours post-MSU mice were treated with 100 mg/kg BCL-XL inhibitor or vehicle control by oral gavage. Sixteen hours later, (B) peritoneal or (C) blood cells were collected and neutrophils enumerated by PI staining and flow cytometry. Data shown were pooled from 2 experiments (n = 10/group; mean ± SEM). All data were analyzed using a 2-tailed Student t test. **P < .01.