Department of Virology, Faculty of Medicine, Imperial College London, St Mary's Campus, Norfolk Place, London W2 1PG, UK.
Science. 2010 Feb 12;327(5967):873-876. doi: 10.1126/science.1183173. Epub 2010 Jan 21.
Viruses are thought to spread across susceptible cells through an iterative process of infection, replication, and release, so that the rate of spread is limited by replication kinetics. Here, we show that vaccinia virus spreads across one cell every 75 minutes, fourfold faster than its replication cycle would permit. To explain this phenomenon, we found that newly infected cells express two surface proteins that mark cells as infected and, via exploitation of cellular machinery, induce the repulsion of superinfecting virions away toward uninfected cells. Mechanistically, early expression of proteins A33 and A36 was critical for virion repulsion and rapid spread, and cells expressing these proteins repelled exogenous virions rapidly. Additional spreading mechanisms may exist for other viruses that also spread faster than predicted by replication kinetics.
病毒被认为通过感染、复制和释放的迭代过程在易感细胞中传播，因此传播速度受到复制动力学的限制。在这里，我们表明，牛痘病毒每 75 分钟跨越一个细胞传播，比其复制周期快四倍。为了解释这一现象，我们发现新感染的细胞表达两种表面蛋白，将细胞标记为感染细胞，并通过利用细胞机制，诱导超感染病毒粒子远离未感染细胞。从机制上讲，早期表达蛋白 A33 和 A36 对于病毒粒子的排斥和快速传播至关重要，并且表达这些蛋白的细胞能够迅速排斥外源性病毒粒子。对于其他传播速度超过复制动力学预测的病毒，可能存在其他传播机制。
