Evidence of escape of SARS-CoV-2 variant B.1.351 from natural and vaccine-induced sera

Cell. 2021 Apr 29;184(9):2348-2361.e6. doi: 10.1016/j.cell.2021.02.037. Epub 2021 Feb 23.

Abstract

The race to produce vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began when the first sequence was published, and this forms the basis for vaccines currently deployed globally. Independent lineages of SARS-CoV-2 have recently been reported: UK, B.1.1.7; South Africa, B.1.351; and Brazil, P.1. These variants have multiple changes in the immunodominant spike protein that facilitates viral cell entry via the angiotensin-converting enzyme-2 (ACE2) receptor. Mutations in the receptor recognition site on the spike are of great concern for their potential for immune escape. Here, we describe a structure-function analysis of B.1.351 using a large cohort of convalescent and vaccinee serum samples. The receptor-binding domain mutations provide tighter ACE2 binding and widespread escape from monoclonal antibody neutralization largely driven by E484K, although K417N and N501Y act together against some important antibody classes. In a number of cases, it would appear that convalescent and some vaccine serum offers limited protection against this variant.

Keywords: ACE2; B.1.351; SARS-CoV-2; South Africa; antibody; escape; neutralization; receptor-binding domain; vaccine; variant.

Publication types

  • Research Support, Non-U.S. Gov't