The therapeutic effect of bovine lactoferrin in the host infected with Helicobacter pylori

Background: It remains unclarified whether bovine lactoferrin (bLF) can exe rt a therapeutic effect on the host infected with Helicobacter pylori. Meth ods: Germfree BALB/c mice were orally inoculated with H. pylori to induce i nfection. Three weeks after infection the mice were given bLF orally once d aily for 2 or 4 weeks and were then kilted to examine the bacterial number in the stomach and the serum antibody titer to H. pylori. To count the numb er of epithelium-bound H. pylori, the resected stomach was agitated in phos phate-buffered saline to remove non-bound H. pylori before bacterial enumer ation. Results: The administration of 10 mg bLF for 3 to 4 weeks decreased the number of H. pylori in the stomach to one-tenth and also exerted a sign ificant inhibitory effect on the attachment of H. pylori to the stomach. As a result, the serum antibody titer to H. pylori, whose level is presumed t o represent the size of the immune response by the host, thereby reflecting the degree of bacterial attack, decreased to an undetectable level. Conclu sions: These findings suggest that bLF exerts an inhibitory effect on colon izing H. pylori by detaching the bacterium from the gastric epithelium and by exerting a direct anti-bacterial effect.