Banfield B W, Leduc Y, Esford L, Schubert K, Tufaro F
Department of Microbiology and Immunology, University of British Columbia, Vancouver, Canada.
J Virol. 1995 Jun;69(6):3290-8. doi: 10.1128/JVI.69.6.3290-3298.1995.
A novel mouse L-cell mutant cell line defective in the biosynthesis of glycosaminoglycans was isolated by selection for cells resistant to herpes simplex virus (HSV) infection. These cells, termed sog9, were derived from mutant parental gro2C cells, which are themselves defective in heparan sulfate biosynthesis and 90% resistant to HSV type 1 (HSV-1) infection compared with control L cells (S. Gruenheid, L. Gatzke, H. Meadows, and F. Tufaro, J. Virol. 67:93-100, 1993). In this report, we show that sog9 cells exhibit a 3-order-of-magnitude reduction in susceptibility to HSV-1 compared with control L cells. In steady-state labeling experiments, sog9 cells accumulated almost no [35S]sulfate-labeled or [6-3H]glucosamine-labeled glycosaminoglycans, suggesting that the initiation of glycosaminoglycan assembly was specifically reduced in these cells. Despite these defects, sog9 cells were fully susceptible to vesicular stomatitis virus (VSV) and permissive for both VSV and HSV replication, assembly, and egress. HSV plaques formed in the sog9 monolayers in proportion to the amount of input virus, suggesting the block to infection was in the virus entry pathway. More importantly, HSV-1 infection of sog9 cells was not significantly reduced by soluble heparan sulfate, indicating that infection was glycosaminoglycan independent. Infection was inhibited by soluble gD-1, however, which suggests that glycoprotein gD plays a role in the infection of this cell line. The block to sog9 cell infection by HSV-1 could be eliminated by adding soluble dextran sulfate to the inoculum, which may act by stabilizing the virus at the sog9 cell surface. Thus, sog9 cells provide direct genetic evidence for a proteoglycan-independent entry pathway for HSV-1, and results with these cells suggest that HSV-1 is a useful reagent for the direct selection of novel animal cell mutants defective in the synthesis of cell surface proteoglycans.
通过筛选对单纯疱疹病毒（HSV）感染具有抗性的细胞，分离出一种在糖胺聚糖生物合成方面存在缺陷的新型小鼠L细胞突变细胞系。这些细胞被称为sog9，它们源自突变的亲本gro2C细胞，而gro2C细胞本身在硫酸乙酰肝素生物合成方面存在缺陷，与对照L细胞相比，对1型单纯疱疹病毒（HSV-1）感染具有90%的抗性（S. Gruenheid、L. Gatzke、H. Meadows和F. Tufaro，《病毒学杂志》67:93 - 100，1993年）。在本报告中，我们表明与对照L细胞相比，sog9细胞对HSV-1的敏感性降低了3个数量级。在稳态标记实验中，sog9细胞几乎没有积累[35S]硫酸盐标记或[6-3H]葡糖胺标记的糖胺聚糖，这表明这些细胞中糖胺聚糖组装的起始过程被特异性降低。尽管存在这些缺陷，sog9细胞对水疱性口炎病毒（VSV）完全敏感，并且允许VSV和HSV进行复制、组装和释放。在sog9单层细胞中形成的HSV空斑与输入病毒的量成比例，这表明感染的阻断发生在病毒进入途径中。更重要的是，可溶性硫酸乙酰肝素并未显著降低HSV-1对sog9细胞的感染，这表明感染不依赖于糖胺聚糖。然而，可溶性gD-1可抑制感染，这表明糖蛋白gD在该细胞系的感染中起作用。通过向接种物中添加可溶性硫酸葡聚糖，可以消除HSV-1对sog9细胞感染的阻断，硫酸葡聚糖可能通过在sog9细胞表面稳定病毒而起作用。因此，sog9细胞为HSV-1的不依赖蛋白聚糖的进入途径提供了直接的遗传学证据，并且对这些细胞的研究结果表明HSV-1是直接筛选在细胞表面蛋白聚糖合成方面存在缺陷的新型动物细胞突变体的有用试剂。
