BERGS V V, HENLE G, DEINHARDT F, HENLE W
J Exp Med. 1958 Oct 1;108(4):561-72. doi: 10.1084/jem.108.4.561.
Efforts were made to elucidate the nature of the resistance to vesicular stomatitis virus (VSV) observed in MCN cultures persistently infected with Newcastle disease, mumps, or 6-6 viruses (MCN(NDV), MCN(Mps) and MCN(6-6), respectively). Cells derived from persistently infected cultures adsorbed VSV to the same extent as their uninfected counterparts. Only a fraction of the adsorbed virus could be recovered from the cells indicating that it enters into an eclipse in all of the cell types. While propagation of VSV in MCN cells is largely inhibited at low pH levels, the resistance of persistently infected cultures could not be ascribed to their increased lactic acid formation. Resistance was not absolute in that a few cells in persistently infected cultures apparently supported VSV reproduction. Furthermore resistance of the cultures was found to be transitory in that the VSV infection gradually gained the upper hand after 2 to 4 weeks of incubation. Addition of ultraviolet-inactivated NDV to MCN cultures induced resistance to VSV as long as the equivalent of at least one ID(50) (for chick embryos) of inactivated virus was provided per cell. Establishment of resistance required some time and its duration depended upon whether or not the free inactivated NDV was removed or neutralized after given adsorption periods. The transitory nature of resistance in persistently infected cultures, or in MCN cells following adsorption of inactivated NDV, is most likely explained by the fact that the cells continue to divide and that the daughter cells are, at least in part, susceptible to VSV. The results are compatible with the conclusion that the resistance observed represents another example of interference between 2 viruses.
研究人员致力于阐明在持续感染新城疫病毒、腮腺炎病毒或6-6病毒（分别为MCN(NDV)、MCN(Mps)和MCN(6-6)）的MCN培养物中观察到的对水疱性口炎病毒（VSV）的抗性本质。来自持续感染培养物的细胞吸附VSV的程度与未感染的对应细胞相同。从细胞中只能回收一小部分吸附的病毒，这表明它在所有细胞类型中都进入了隐蔽期。虽然VSV在MCN细胞中的增殖在低pH水平下受到很大抑制，但持续感染培养物的抗性不能归因于它们乳酸生成的增加。抗性并非绝对，因为持续感染培养物中的一些细胞显然支持VSV繁殖。此外，发现培养物的抗性是暂时的，因为在孵育2至4周后，VSV感染逐渐占上风。向MCN培养物中添加紫外线灭活的NDV可诱导对VSV的抗性，只要每个细胞提供相当于至少一个ID(50)（对鸡胚）的灭活病毒。抗性的建立需要一些时间，其持续时间取决于在给定吸附期后游离的灭活NDV是否被去除或中和。持续感染培养物或吸附灭活NDV后的MCN细胞中抗性的短暂性质，很可能是因为细胞继续分裂，并且子细胞至少部分对VSV敏感。这些结果与观察到的抗性代表两种病毒之间干扰的另一个例子的结论一致。
