The possible interaction of the neutrophil-activating protein of Helicobacter pylori with target cell glycoconjugates was investigated by the binding of 125I-labeled recombinant protein to glycosphingolipids from human neutrophils in solid phase assays. Thereby, a distinct binding of the neutrophil-activating protein to four bands in the acid glycosphingolipid fraction from human neutrophils was detected, whereas no binding to the non-acid glycosphingolipids or polyglycosyl ceramides from these cells was obtained. When using glycosphingolipids not present in the cell membrane of human neutrophils, it was found that the neutrophil-activating protein also bound to sulfated glycosphingolipids as sulfatide and sulfated gangliotetraosyl ceramide. Comparison of the binding preferences of the protein to reference glycosphingolipids from other sources suggested that in human granulocytes, the neutrophil-activating protein of H. pylori preferentially recognizes glycoconjugates with a terminally unsubstituted NeuAcalpha3Galbeta4GlcNAcbeta3Galbeta4GlcNAcbeta sequence.