Effect of heparin binding on Helicobacter pylori resistance to serum

The objective of this study was to evaluate the effect of heparin binding to Helicobacter pylori cells on their survival in the presence of fresh rabbit serum with or without active complement components. Three H. pylori strains were compared and the amounts of heparin added reflected the physiological concentrations that can be found in animal tissues. No growth of H. pylori was noted in the presence of serum. Serum with or without active complement produced a reduction in c.f.u. for strains SPM 326, CCUG 17874(T) and SS1. However, addition of heparin resulted in increased survival of bacterial cells in serum with or without active complement. It appears that heparin binding to H. pylori can prevent bacterial cell death due to the alternative complement system. Heparin binding could also protect from heated serum (complement-inactivated), indicating protection from other serum components besides complement. In vivo, the process of heparin binding could possibly result in facilitated colonization due to a higher survival rate.