Protective Mechanism of Recombinant Bactericidal Permeability-increasing Protein 21 in Rat Endotoxemia / 中华医院感染学杂志

ABSTRACT

OBJECTIVE To investigate the protective mechanism of recombinant bactericidal permeability-increasing protein 21(rBPI21) in rat endotoxemia.METHODS The different dosage of rBPI21 in endotoxemia rats was injected and the changes in lipopolysaccharide(LPS), lipopolysaccharide binding protein(LBP) and tumor necrosis factor ?(TNF?) contents in blood of different group rats were continuously observed.RESULTS At 6 and 12 hours,the levels of LPS in rBPI21 treatment 1 group(rBPI21 dosage 0.625 mg/kg) were significantly lower than those in endotoxin group at the same time.Serum LBP and TNF? in rBPI21 treatment 1 group were both lower than those in endotoxin group at any time point.Compared with the endotoxin group,the levels of LPS,LBP,and TNF? in rBPI21 treatment 2,3 and 4 groups(rBPI21 dosage 1.25 mg/kg,2.5mg/kg,and 5.0mg/kg,respectively) markedly dropped at any time points,the survival rates were increased from 16.7%(endotoxin group) to 58.3%,91.7% and 100%(rBPI21 treatment 2,3,and 4 groups) individually.CONCLUSIONS The protection of rBPI21 in endotoxemia rats is primarily achieved through neutralizing LPS,decreasing LPS activity in vivo and inhibiting LBP and TNF-? synthesis.