Department of Microbiology, The University of Texas at Austin, Austin, Texas 78712.
Infect Immun. 1971 Feb;3(2):268-73. doi: 10.1128/iai.3.2.268-273.1971.
The development of resistance of outbred white mice to two plaque size variants of Sindbis virus was studied as a function of host age. A sudden drop in mortality occurred over a 3-day period. As little as 1 plaque-forming unit (PFU) per mouse was lethal in 1-day-old animals, whereas inocula of 10(9) PFU per mouse failed to produce high mortality in weanlings. A comparison of viral growth kinetics shows that early replication was similar in newborns and weanlings but that after 6 to 8 hr the production rate and, therefore, the maximal viral titer were suppressed in weanlings. The data demonstrate a lethal viral threshold. Titers in excess of this level lead to mortality, whereas those below it allow survival.
本研究旨在探讨年龄因素对野白化鼠抵抗两种辛德比斯病毒噬菌斑大小变体能力的影响。结果发现，死亡率在 3 天内突然下降。在 1 日龄动物中，每只老鼠只需 1 个噬菌斑形成单位（PFU）即可致命，而在 10（9）PFU 每只老鼠的接种物未能在断奶幼鼠中产生高死亡率。病毒生长动力学的比较表明，新生儿和断奶幼鼠的早期复制相似，但在 6 至 8 小时后，断奶幼鼠的产率（因此，最大病毒滴度）受到抑制。数据表明存在致命的病毒阈值。超过此水平的滴度会导致死亡，而低于此水平的滴度则允许存活。
