Active and inactive influenza virus induction of tumor necrosis factor-alpha and nitric oxide in J774.1 murine macrophages: modulation by interferon-gamma and failure to induce apoptosis.
Infection of J774.1 murine macrophages by influenza A virus (IAV) induces two major responses, production of host defense molecules and death by apoptosis. We investigated whether induction of two cytotoxic compounds, tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO), directly caused IAV-induced apoptosis, and whether induction could be modulated by interferon-gamma (IFN-gamma) or the replication competence of the virus. Live IAV potently induced production of both TNF-alpha and NO, but UV inactivated virus was a poor inducer of both molecules. When cells were pre-treated with IFN-gamma, inactive IAV became as effective an inducer of NO, but not TNF-alpha, as live IAV. Amantadine, which antagonizes viral entry and replication, partly inhibited TNF-alpha and NO production in unprimed cells, but did not inhibit NO in IFN-gamma primed cells. IAV-induced cytotoxicity was not due to the induction of TNF-alpha or NO. Cells were insensitive to either TNF-alpha-containing supernatants or to recombinant TNF-alpha. Anti-TNF-alpha antibody did not protect cells from IAV-induced cell death, and anti-oxidants that inhibited TNF-alpha production also failed to increase cell survival. Inhibitors of NO production did not protect from IAV-induced cell death, either alone or in combination with superoxide dismutase (SOD). We conclude that, even though IAV was a potent inducer of TNF-alpha and NO in macrophages, IAV-induced apoptosis was not mediated directly by them. Importantly, viral replication was not required for the induction of TNF-alpha or NO, and the action of inactive IAV could be potentiated by IFN-gamma.
Radiation Pathophysiology and Toxicology Department, Armed Forces Radiobiology Research Institute, 8901 Wisconsin Avenue, Bethesda, MD 20889, USA.
Leslie C
LC
McKinney
Sandra J
SJ
Galliger
R Joel
RJ
Lowy
D000547:Amantadine / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000276:immunology; D000975:Antioxidants / Q000494:pharmacology; D000998:Antiviral Agents / Q000494:pharmacology; D017209:Apoptosis; D002460:Cell Line; D017077:Culture Media, Conditioned; D009980:Influenza A virus / Q000276:immunology / Q000502:physiology*; D007371:Interferon-gamma / Q000494:pharmacology*; D008264:Macrophages / Q000276:immunology / Q000378:metabolism / Q000502:physiology / Q000821:virology*; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000378:metabolism; D052247:Nitric Oxide Synthase Type II; D011994:Recombinant Proteins / Q000494:pharmacology; D013482:Superoxide Dismutase / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis* / Q000276:immunology / Q000378:metabolism / Q000494:pharmacology; D015854:Up-Regulation; D038301:Virus Inactivation / Q000528:radiation effects; D014779:Virus Replication / Q000235:genetics / Q000528:radiation effects
D000906:Antibodies; D000975:Antioxidants; D000998:Antiviral Agents; D017077:Culture Media, Conditioned; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; D000547:Amantadine; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; C496317:Nos2 protein, mouse; D013482:Superoxide Dismutase