Protective effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) against various microbial...

Protective effect of recombinant human granulocyte colony-stimulating factor (rG-CSF) on microbial infections was studied in cyclophosphamide (CPA)-induced neutropenic mice. The neutropenic mice showed severely decreased resistance against systemic infections of Pseudomonas aeruginosa, Escherichia coli, Serratia marcescens, Staphylococcus aureus, and Candida albicans. When such mice were injected subcutaneously with rG-CSF on four consecutive days beginning the day after CPA injection, the decreased anti-microbial resistance of the mice was restored to the level of that in normal mice. The anti-infective effect of rG-CSF was dose-dependent and the 50% effective doses (ED50) in various microbial infections tested were 1-10 micrograms/kg/day. The results suggest that rG-CSF is useful for protection of neutropenic patients from microbial infections.