Abstract
As evidenced by electron microscopy, unopsonised bacteria of some Helicobacter pylori strains were readily taken into cytoplasmic vacuoles of human neutrophils; those of other strains were only rarely absorbed. The strains engulfed like this also induced strong oxidative burst reactions in neutrophils, as measured by chemiluminescence. This has been associated with peptic ulcer disease, in the past. The ultrastructural interaction patterns agreed with the reaction patterns shown by chemiluminescence.