Factors influencing virulence and plaque properties of attenuated Venezuelan equine encephalomyelitis virus populations.
A minority of stable large-plaque virus increased proportionally in stored unstable attenuated (9t) Venezuelan equine encephalomyelitis virus populations. L-cell-grown progeny (9t2) of stored 9t showed large amounts of large-plaque virus and increased virulence. Small-plaque virus inhibited large-plaque virus but not the reverse. Serial passage of small-plaque virus from 9t2 yielded a strain (20t) that was more attenuated than 9t.
D000818:Animals; D001103:Arboviruses / Q000254:growth & development / Q000302:isolation & purification / Q000472:pathogenicity*; D004683:Encephalomyelitis, Equine / Q000382:microbiology; D066298:In Vitro Techniques; D007739:L Cells; D051379:Mice; D014687:Venezuela; D014774:Virulence
J Virol. 1967 Jun;1(3):453-9
5623966