ABSTRACT
Live Newcastle disease virus (NDV) was used to investigate the in vitro effects of a viral infection on phagocytosis, chemiluminescence generation, superoxide production, oxygen consumption, NADPH-oxidase activity, and intracellular killing of bacteria by Ficoll-Hypaque separated human neutrophils. Phagocytosis of oil red O particles by NDV-treated PMN was inhibited by 50%. Chemiluminescence by PMN was inhibited 79% after zymosan stimulation and 86% after tetradeconyl phorbol acetate stimulation. Superoxide generation was inhibited by 68%. Oxygen consumption was inhibited in the presence of NDV by 37% after stimulation with phorbol myristate acetate, while membrane-associated NADPH-enzyme activity was decreased by 19%. The percent of surviving intracellular S. aureus was significantly elevated in NDV-treated PMN after 60 and 120 min of incubation. Purified bacterial neuraminidase markedly suppressed chemiluminescence, while neuraminic acid blocked the effects of the virus. These observations suggest that infections with myxoviruses may suppress a number of vital neutrophil functions. It appears that the effects may be partly mediated by the interaction of viral neuraminidase with the external neutrophil membrane.
Subject(s)
Neutrophils/metabolism , Newcastle Disease/metabolism , Adult , Animals , Birds , Blood Bactericidal Activity , Humans , Luminescent Measurements , Middle Aged , NADH, NADPH Oxidoreductases/metabolism , NADPH Oxidases , Neuraminidase/pharmacology , Neutrophils/microbiology , Newcastle Disease/microbiology , Newcastle disease virus/radiation effects , Oils , Oxygen Consumption , Phagocytosis , Superoxides/metabolism , Tetradecanoylphorbol Acetate/pharmacology , Zymosan/pharmacologyABSTRACT
The effects of Newcastle disease, herpes simplex, vaccinia, encephalomyocarditis, vesicular stomatitis and reoviruses on in vitro function of neutrophils were studied in Ficoll-Hypaque-separated polymorphonuclear leukocytes (PMN) employing the technique of luminol-dependent chemiluminescence. Newcastle disease, herpes simplex vaccinia, and reoviruses depressed chemiluminescence by 98, 65, 46, and 29%, respectively, while encephalomyocarditis and vesicular stomatitis viruses had no inhibitory effect. None of the viruses affected phagocytosis or PMN viability. These observations suggest significant alteration of neutrophil function by interaction with several viruses in in vitro settings. It is suggested that similar changes in PMN function may occur during in vivo viral infection.
