Lactoferrin and desferrioxamine are ineffective in the treatment of Helicobacter pylori infection and may enhance H-pylori growth and gastric inflammation in mice

To evaluate the efficacy of bovine lactoferrin (BLf), recombinant human lactoferrin (rHLf) and desferrioxamine against Helicobacter pylori in vitro and in mice and also to determine whether BLf or rHLf alter gastric inflammation. In vitro: Broth dilution susceptibility tests were performed using different concentrations of desferrioxamine, BLf and rHLf. Murine trials: In the prevention trial, C57BL/6 female mice were treated with BLf or rHLF, and then infected with the SS1 strain of H. pylori. In the treatment trial, mice were gavaged with either BLf, rHLf or desferrioxamine. In addition, gastric myeloperoxidase activity (MPO) was measured to assess gastric inflammation. Desferoxamine was found to have a direct bactericidal effect, while BLf and rHLf only partially suppressed H. pylori growth in vitro. However, in both prevention and treatment trials all three forms of treatment failed to reduce H. pylori load in mice. Gastric MPO activity and H. pylori load were noted to be higher with lactoferrin treatments. Our study does not support the use of BLf or rHLF in the treatment of human H. pylori infection. Interestingly, H. pylori growth and gastric inflammation appear to be enhanced by lactoferrin treatment. The mouse model is ideal for testing novel H. pylori eradicating agents.