Nitric oxide production is increased during murine vaccinia virus infection, but may not be essential for virus clearance.
Recent reports have highlighted a potential antiviral activity for nitric oxide (NO). The purpose of this study was to investigate the production of NO in mice during vaccinia virus (VV) or herpes simplex virus type 1 infection, and to assess the role of NO in clearance of VV. Reactive nitrogen intermediates (RNI; NO and its stable oxidation products, nitrite and nitrate) were significantly elevated in the plasma of mice infected with these viruses. Furthermore, spleen cells from virus-infected mice produced elevated RNI levels following stimulation in vitro with LPS. NO production during VV infection was critically dependent on the cytokines tumor necrosis factor and interferon-gamma, and on the presence of both CD4+ and CD8+ T lymphocytes. Treatment of VV-infected mice with the nitric oxide synthase inhibitor N(G)-methyl-L-arginine did not alter the course of infection, suggesting that NO may not be essential for the clearance of this virus.
Rolph
M S
MS
Division of Cell Biology, John Curtin School of Medical Research, Canberra, Australia.
Ramshaw
I A
IA
Rockett
K A
KA
Ruby
J
J
Cowden
W B
WB
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D002478:Cells, Cultured; D004481:Ectromelia virus; D004482:Ectromelia, Infectious / Q000276:immunology; D005260:Female; D007371:Interferon-gamma / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D013154:Spleen / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000502:physiology; D014615:Vaccinia / Q000097:blood / Q000276:immunology*; D014616:Vaccinia virus
D014409:Tumor Necrosis Factor-alpha; D009569:Nitric Oxide; D007371:Interferon-gamma; D019001:Nitric Oxide Synthase