Inhibitory effects of human neutrophil functions by the 45-kD glycoprotein derived from the parasitic nematode Trichinella spiralis

Aim: We evaluated the effect of the 45-kD protein of Trichinella spiralis (gp45), purified by affinity chromatography, on random migration and chemotaxis, the oxidative metabolism of human neutrophils and on the CD11b upregulation induced by formyl-methionyl-leucyl-phenylalanine (f-MLP). Methods: Donor neutrophils incubated with different amounts of gp45 (0.5, 1, 1.5, 2 mu g/ml) or buffer and the random migration and chemotaxis, evaluated by means of a special technique of image analysis, and the chemiluminescence response to f-MLP or phorbol myristate acetate (PMA) were analyzed. The effect on CD11b upregulation was assessed incubating cells with the protein, when activating them with f-MLP. Results: The results showed that gp45 inhibited both random and stimulated migrations, and reduced the response to f-MLP and PMA. Furthermore, gp45 significantly reduced the upregulation of the CD11b induced by f-MLP. Conclusion: The results show that gp45 inhibits PMN in different functions, suggesting an anti-inflammatory action. Copyright (C) 2000 S. Karger AG, Basel.