preprints.org > life sciences > microbiology > doi: 10.20944/preprints202203.0376.v1

Preprint Review Version 1 Preserved in Portico This version is not peer-reviewed

Version 1 : Received: 28 March 2022 / Approved: 29 March 2022 / Online: 29 March 2022 (08:44:09 CEST)

With the emergence of COVID-19 pandemic in 2019, the world saw a humungous loss of human life and economic resources globally but also the rapid appearance of SARS-CoV-2 variants which have exhibited a higher transmissibility and/or virulence and which also evade immune system to such an extent that it raises a big question mark on the efficacy of current diagnostics, vaccines and convalescent plasma and mAb therapies. This has been attributed to the emergence of huge spectrum of mutations, especially in the virus’s spike (S) protein, occurring in regions harboring high concentration of B cell epitopes thus allowing neutralizing antibody escape. The mutations resulting in ACE 2 receptor recognition failure (T19R), unfavorable electrostatic interactions (E484K), structural change (∆69-70), disruption of hydrogen bonds, salt bridges or hydrophobic interactions (K417N, N501Y, ∆Y145) and change in orientation (N501Y) cause strong immune evasion by these variants. Further, the recent emergence of Omicron with more than 30 mutations in the S protein VOC allows it to escape and fail diagnosis as well as immune system and the protection generated by different vaccination regimes. Yet Omicron may not be the end of the story. This review presents an insight of the immunity escape and its mechanisms followed by different SARS-CoV-2 variant of concerns.

SARS-CoV-2; Mutations; Omicron; Delta; Variants of Concern; Variants of Interest; Immunity Escape; Mechanisms

LIFE SCIENCES, Microbiology