ANTIBACTERIAL SYSTEM GENERATED BY LACTOFERRIN IN MICE IN-VIVO IS PRIMARILY A KILLING SYSTEM

A single dose of bovine lactoferrin (BLF) was given intravenously (i.v .) to CFW mice 24 hours (h) prior to the i.v. injection of the E. coil lethal dose (LD100). ELF strongly accelerated the clearance rate of E . coli from the blood as well as its killing rate in the liver, lungs, spleen and kidney. The highest clearing and killing rate was found 5 h after E. coil LD100 injection. The most intensive killing in the org ans examined was found in the lungs and kidney. Analysis of organs of i.v. ELF-stimulated mice which survived up to day 30 after the infecti on by E. coli showed that not all animals were definitely pathogen-fre e. It was concluded that the defense system generated by ELF in mice i n vivo is primarily a bacteria-killing one. The participation and coop eration of reticulo-endothelial (RE)-macrophages and granulocytes in t he phagocytosis and killing of E. coil may thus be related to the prot ective activity of LF.