Helicobacter pylori secretes a chemotactic factor for monocytes and neutrophils.

Helicobacter pylori is associated with an inflammatory reaction in the stomach and duodenum, yet the mechanism of this inflammatory infiltrate is unknown. The ability of Helicobacter pylori to secrete a factor that attracts leucocytes is investigated. Helicobacter pylori conditioned supernatant attracted neutrophils and monocytes with 50-100% of the activity of control chemotactic factor, 10(-8) M formyl-methionine-leucine-phenylalanine. Strains derived from individuals with ulcer or non-ulcer associated H pylori infections displayed similar chemotactic activity. Preliminary characterisation shows that the factor has a molecular weight of less than 3000, is heat stable, is acid resistant, and can be diluted at least 10-fold. Checkerboard analysis confirmed that the activity was chemotactic rather than chemokinetic. This chemotactic activity could play a role in the pathogenesis of Helicobacter pylori gastritis.