Resistance to alpha/beta interferons correlates with the epizootic and virulence potential of Venezuelan equine encephalitis viruses and is determined by the 5' noncoding region and glycoproteins.
We compared the alpha/beta interferon (IFN-alpha/beta) sensitivities of the TC-83 vaccine strain and 24 enzootic and epizootic Venezuelan equine encephalitis (VEE) isolates. The IFN-resistant or -sensitive phenotype correlated well with epizootic or enzootic potential. IFN-alpha/beta resistance of Trinidad donkey (TRD) virus correlated with virulence determinants in the 5' noncoding region and glycoproteins. Infection of mice lacking a functional IFN system with the IFN-sensitive TC-83 virus resulted in disease equivalent to that produced by the virulent, IFN-resistant TRD virus, further demonstrating that IFN resistance contributes to VEE virus virulence and is a biological marker of epizootic potential.
Spotts
D R
DR
Arbovirus Diseases Branch, Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Fort Collins, Colorado 80522, USA.
Reich
R M
RM
Kalkhan
M A
MA
Kinney
R M
RM
Roehrig
J T
JT
D000818:Animals; D002460:Cell Line; D003588:Cytopathogenic Effect, Viral; D004352:Drug Resistance, Microbial / Q000235:genetics; D004666:Encephalitis Virus, Venezuelan Equine / Q000235:genetics / Q000302:isolation & purification / Q000472:pathogenicity*; D004685:Encephalomyelitis, Venezuelan Equine / Q000662:veterinary* / Q000821:virology; D006023:Glycoproteins / Q000235:genetics; D006734:Horse Diseases / Q000821:virology*; D006736:Horses; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology*; D051379:Mice; D014774:Virulence / Q000235:genetics; D015047:Zoonoses / Q000821:virology
D006023:Glycoproteins; D007370:Interferon Type I