Neutrophil-induced immunoglobulin binding to erythrocytes involves proteolytic and oxidative injury.
Neutrophil-induced alterations in feline erythrocytes were studied to better understand the pathogenesis of erythrocyte destruction associated with inflammatory diseases. As in previous studies, addition of superoxide dismutase/catalase to a coculture of erythrocytes and activated neutrophils attenuated neutrophil-induced immunoglobulin G (IgG) binding. However, incubation of erythrocytes with hydrogen peroxide or neutrophil-derived anuclear cytoplasts (neutroplasts) failed to induce IgG binding. Addition of phenylmethylsulfonyl fluoride, a serine protease inhibitor, to the erythrocyte-neutrophil coculture attenuated IgG binding. These observations suggest that neutrophil-derived serine protease activity is involved in IgG binding to erythrocytes. Further, incubation of erythrocytes with serine proteases, but not metalloproteases or sulfhydryl proteases, induced immunoglobulin binding. Freeze-fracture replicas of the erythrocyte membrane failed to demonstrate clustering of band 3 protein, suggesting that spatial rearrangement of band 3 protein was not the cause of the IgG binding. Neutrophil-induced IgG binding due to the combined action of proteases and oxidants may explain the accelerated destruction of erythrocytes in inflammatory diseases.
Weiss
D J
DJ
Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Minnesota, St. Paul 55108.
Aird
B
B
Murtaugh
M P
MP
D000818:Animals; D001457:Anion Exchange Protein 1, Erythrocyte / Q000032:analysis; D002415:Cats; D002478:Cells, Cultured; D010450:Endopeptidases / Q000494:pharmacology*; D004912:Erythrocytes / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure; D005614:Freeze Fracturing; D007074:Immunoglobulin G / Q000378:metabolism*; D008854:Microscopy, Electron; D009504:Neutrophils / Q000166:cytology / Q000502:physiology*; D016877:Oxidants / Q000494:pharmacology*; D010664:Phenylmethylsulfonyl Fluoride / Q000494:pharmacology; D011485:Protein Binding; D012697:Serine Endopeptidases / Q000502:physiology
D001457:Anion Exchange Protein 1, Erythrocyte; D007074:Immunoglobulin G; D016877:Oxidants; D010664:Phenylmethylsulfonyl Fluoride; D010450:Endopeptidases; D012697:Serine Endopeptidases