CONTROL OF FECAL PERITONEAL INFECTION IN MICE BY COLONY-STIMULATING FACTORS

Granulocyte colony-stimulating factor (G-CSF) recruits and primes neut rophilic granulocytes. The role of endogenous and exogenous G-CSF was examined in a murine fecal peritoneal infection model characterized by rapid production of high levels of circulating G-CSF, Pretreatment wi th anti-murine G-CSF for 5 days reduced neutrophil counts by 50% and s ensitized mice to sublethal peritonitis. There mere more aerobic bacte ria in livers of antiserum-pretreated animals but fewer neutrophils in peritoneal cavities, Pretreatment with 100 mu g/kg recombinant murine G-CSF intravenously for 2 days raised neutrophil counts 5-fold and si gnificantly protected animals against lethal peritonitis. A similar pr ophylactic administration of murine granulocyte-macrophage (GM)-CSF ne ither augmented leukocyte numbers nor protected infected mice, These r esults show a dissociation between the pharmacologic properties of GM- CSF and G-CSF and demonstrate the crucial role of endogenous G-CSF in controlling neutrophil-dependent defense against bacterial invasion in infection.