Analysis of SARS-CoV-2 variants B.1.617: host tropism, proteolytic activation, cell–cell fusion, and neutralization sensitivity

Emerging Microbes and Infections

Yinan Jiang¹  Lili Qin¹  Yi Shi²  Weijin Huang³  Zhimin Cui³  Haixin Wang³  Ruxia Ding³  Youchun Wang³  Jianhui Nie³  Lingling Nie³  Qiong Lu³  Jiayi Li³  Li Zhang³  Yuanling Yu³  Qianqian Li³  Ziteng Liang³  Shuo Liu³  Tao Li³  Yue Zhang³  Jiajing Wu³  Fei Jiang³  Wenbo Xu⁴ 

[1] Acro Biosystems, Inc., Beijing, People’s Republic of China;CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, People’s Republic of China;Division of HIV/AIDS and Sex-transmitted Virus Vaccines, Institute for Biological Product Control, National Institutes for Food and Drug Control (NIFDC), Beijing, People's Republic of China;National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing, People’s Republic of China;

关键词: SARS-CoV-2 variants;    delta;    B.1.617;    infectivity;    cell–cell fusion;    neutralization;   

DOI  :  10.1080/22221751.2022.2054369

来源: DOAJ

【 摘 要 】

SARS-CoV-2 has caused the COVID-19 pandemic. B.1.617 variants (including Kappa and Delta) have been transmitted rapidly in India. The transmissibility, pathogenicity, and neutralization characteristics of these variants have received considerable interest. In this study, 22 pseudotyped viruses were constructed for B.1.617 variants and their corresponding single amino acid mutations. B.1.617 variants did not exhibit significant enhanced infectivity in human cells, but mutations T478K and E484Q in the receptor binding domain led to enhanced infectivity in mouse ACE2-overexpressing cells. Furin activities were slightly increased against B.1.617 variants and cell–cell fusion after infection of B.1.617 variants were enhanced. Furthermore, B.1.617 variants escaped neutralization by several mAbs, mainly because of mutations L452R, T478K, and E484Q in the receptor binding domain. The neutralization activities of sera from convalescent patients, inactivated vaccine-immunized volunteers, adenovirus vaccine-immunized volunteers, and SARS-CoV-2 immunized animals against pseudotyped B.1.617 variants were reduced by approximately twofold, compared with the D614G variant.

【 授权许可】

Unknown