The 501Y.V2 variants of SARS-CoV-2 containing multiple mutations in spike are now dominant in South Africa and are rapidly spreading to other countries. Here, experiments with 18 pseudotyped viruses showed that the 501Y.V2 variants do not confer increased infectivity in multiple cell types except for murine ACE2-overexpressing cells, where a substantial increase in infectivity was observed. Notably, the susceptibility of the 501Y.V2 variants to 12 of 17 neutralizing monoclonal antibodies was substantially diminished, and the neutralization ability of the sera from convalescent patients and immunized mice was also reduced for these variants. The neutralization resistance was mainly caused by E484K and N501Y mutations in the receptor-binding domain of spike. The enhanced infectivity in murine ACE2-overexpressing cells suggests the possibility of spillover of the 501Y.V2 variants to mice. Moreover, the neutralization resistance we detected for the 501Y.V2 variants suggests the potential for compromised efficacy of monoclonal antibodies and vaccines.

SARS-CoV-2 的 501Y.V2 变种包含多个刺突突变，目前在南非占主导地位，并迅速传播到其他国家。在这里，使用 18 种假型病毒进行的实验表明，501Y.V2 变体不会在多种细胞类型中增加感染性，但小鼠 ACE2 过表达细胞除外，在小鼠 ACE2 过表达细胞中观察到感染性大幅增加。值得注意的是，501Y.V2 变体对 17 种中和单克隆抗体中的 12 种的敏感性显着降低，并且对于这些变体，来自恢复期患者和免疫小鼠的血清的中和能力也降低。中和抵抗主要是由spike受体结合域的E484K和N501Y突变引起的。小鼠 ACE2 过表达细胞的感染性增强表明 501Y.V2 变体有可能溢出到小鼠身上。此外，我们检测到的 501Y.V2 变体的中和抗性表明单克隆抗体和疫苗的功效可能会受到损害。