[The study on the role of modeling peptides derived from bactericidal/permeability increasing protein on the endotoxin neutralization].

OBJECTIVE

To observe the role of four modeling peptides (10342, 10343, 10344, 10345) derived from bactericidal/permeability increasing protein (BPI) in neutralizing endotoxin (LPS) in vitro and in vivo.

METHODS

Quantitative limulus amoebocyte lysate assay was employed to evaluate the capacity of BPI peptides in neutralizing endotoxin in vitro. The protective capacity of the peptides was observed in mice challenged with endotoxin by intravenous administration via the tail vein. The influence of the peptides on serum TNFalpha and IL-6 levels in rats with endotoxemia were also observed.

RESULTS

All of the four peptides possessed endotoxin-neutralizing capacity which was strengthened along with the increase in their concentration. Among the peptides, 10342 is the strongest one. All of the peptides had strong power to protect mice from endotoxin with 90% protective rate. In the rats with endotoxemia, the four peptides could reduce the levels of serum TNFalpha and IL-6 significantly at different time-points.

CONCLUSION

Four BPI modeling peptides possessed not only endotoxin-neutralizing capacity in vitro, but also potential protective capacity in animals challenged with endotoxin.