Fig 5.

Depletion of Gr1⁺ cells increases mortality during C. difficile colitis. Mice received a single dose of clindamycin on day −1, followed by infection with C. difficile VPI10463 the next day. Mice received three doses of RB6-8C5 antibody (anti-Gr1, 0.3 mg/dose) or PBS every other day starting on day −1. (A) Mice (n = 10/group) were followed for survival. The log-rank (Mantel-Cox) statistical test was used. (B) The burden of C. difficile in the cecum of animals treated with RB6-8C5 or PBS was quantified on days 1 and 2. In panels A and B, results are pooled from at least two independent experiments. (C) Mice received two doses of RB6-8C5 or PBS on days −1 and 1. On day 2 postinfection, bacterial counts in the mesenteric lymph nodes were determined. (D and E) Mice were infected with C. difficile 1 day following clindamycin and either RB6-8C5 or PBS administration. On day 1 postinfection, the percentages of neutrophils and monocytes were assessed in the cLP of mice treated with RB6-8C5 or PBS and found to be significantly reduced.