COLD ADAPTATION OF HUMAN ROTAVIRUSES

三株人轮状病毒细胞培养分离株(D株[VP7：1，VP4：1A]， DS-1[VP7：2，VP4：1B]和202[VP7：4，VP4：1B])以及两个人类x 人轮状病毒重组体(Wa x P[VP7：3，VP4：1A]和Wa x DS-1 [VP7：2，VP4：1A])已成功适应在初生代生长 非洲绿猴肾细胞在30℃的亚最适温度 摄氏度、28摄氏度或26摄氏度这些轮状病毒株 冷适应以确定冷适应(Ca)突变体 通过这种策略选择的是衰减的，适合在现场使用 病毒疫苗。D和WAxP菌株传代10次 在28摄氏度或26摄氏度，正在进行菌斑纯化。 不同温度下菌斑形成效率的分析 确定了26摄氏度冷适应D菌株确实是一种病例 突变；它在26摄氏度产生斑块，而它的亲本没有。 此外，这个突变体还对温度敏感，有一个关闭 菌斑形成温度37摄氏度DS-1菌株 (在28℃下传代12次)和Wa x DS-1重配子(传代 在28摄氏度下10次)也在进行菌斑纯化。已选择 人轮状病毒包括D、WAxP和WAXDS-1 成功地适应了DBS-FRhL-2细胞的生长，是一种 适合于制备用于人类的疫苗的底物。

Three human rotavirus cell-culture isolates (strains D [VP7:1, VP4:1A], DS-1 [VP7:2, VP4:1B], and 202 [VP7:4, VP4:1B]) as well as two human x human rotavirus reassortants (Wa x P [VP7:3, VP4:1A] and Wa x DS-1 [VP7:2, VP4:1A]) have been successfully adapted to grow in primary African Green monkey kidney cells at the suboptimal temperature of 30 degrees C, 28 degrees C, or 26 degrees C. These rotavirus strains were cold-adapted in order to determine whether cold-adapted (ca) mutants selected by this strategy are attenuated and suitable for use in a live virus vaccine. The D and the Wa x P strains were passaged 10 times either at 28 degrees C or 26 degrees C and are being plaque-purified. Analysis of the efficiency of plaque formation at various temperatures established that the 26 degrees C cold-adapted D strain is indeed a ca mutant; it produced plaques at 26 degrees C, whereas its parent did not. In addition, this mutant is also temperature sensitive having a shut-off temperature for plaque formation of 37 degrees C. The DS-1 strain (passaged 12 times at 28 degrees C) and Wa x DS-1 reassortant (passaged 10 times at 28 degrees C) are also being plaque-purified. Selected human rotaviruses including the D, Wa x P, and Wa x DS-1 have successfully been adapted to growth in DBS-FRhL-2 cells, which is a cell substrate suitable for preparation of vaccines for use in humans.