Mettenleiter T C, Schreurs C, Zuckermann F, Ben-Porat T, Kaplan A S
Department of Microbiology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232.
J Virol. 1988 Aug;62(8):2712-7. doi: 10.1128/JVI.62.8.2712-2717.1988.
Deletion mutants of pseudorabies virus unable to express glycoprotein gIII, gI, or gp63 or double and triple mutants defective in these glycoproteins were constructed, and their virulence for day-old chickens inoculated intracerebrally was determined. Mutants of wild-type pseudorabies virus defective in glycoprotein gIII, gI, or gp63 were only slightly less virulent (at most, fivefold) for chickens than was the wild-type virus. However, mutants defective in both gIII and gI or gIII and gp63 were avirulent for chickens, despite their ability to grow in cell culture in vitro to about the same extent as mutants defective in gIII alone (which were virulent). These results show that gIII plays a role in virulence and does so in conjunction with gI or gp63. The effect of gIII on virulence was also shown when the resident gIII gene of variants of the Bartha vaccine strain (which codes for gIIIB) was replaced with a gIII gene derived from a virulent wild-type strain (which codes for gIIIKa); gIIIKa significantly enhanced the virulence of a variant of the Bartha strain to which partial virulence had been previously restored by marker rescue. Our results show that viral functions that play a role in the virulence of the virus (as measured by intracerebral inoculation of chickens) may act synergistically to affect the expression of virulence and that the ability of the virus to grow in cell culture is not necessarily correlated with virulence.
构建了无法表达糖蛋白gIII、gI或gp63的伪狂犬病病毒缺失突变体，以及在这些糖蛋白方面存在缺陷的双突变体和三突变体，并测定了它们对脑内接种的一日龄雏鸡的毒力。在糖蛋白gIII、gI或gp63方面存在缺陷的野生型伪狂犬病病毒突变体对雏鸡的毒力仅比野生型病毒略低（最多五倍）。然而，gIII和gI或gIII和gp63双缺陷的突变体对雏鸡无毒，尽管它们在体外细胞培养中的生长能力与仅gIII缺陷的突变体（具有毒力）大致相同。这些结果表明，gIII在毒力中起作用，并且与gI或gp63协同发挥作用。当用来自强毒野生型毒株（编码gIIIKa）的gIII基因替换Bartha疫苗株变体（编码gIIIB）的常驻gIII基因时，也显示了gIII对毒力的影响；gIIIKa显著增强了Bartha株变体的毒力，该变体先前已通过标记拯救恢复了部分毒力。我们的结果表明，在病毒毒力中起作用的病毒功能（通过脑内接种雏鸡来衡量）可能协同作用以影响毒力的表达，并且病毒在细胞培养中的生长能力不一定与毒力相关。
