Do mutations in the SARS-CoV-2 spike protein enhances viral infectivity?


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Disclaimer: This is a summary of an article that is in a preprint and has not been peer reviewed.

Authors in a pre-peer reviewed publication analyzed the Spike gene sequences of SARS-CoV-2 submitted to the Global Initiative on Sharing All Influenza Data (GISAID) database (https://nextstrain.org/ncov). They used a lentiviral pseudotype neutralizing antibody assay to evaluate the neutralizing sensitivity of the S-D614 and S-G614 mutation to convalescent sera from COVID-19 patients. Firstly, they found that the entry efficiency of the S-G614 pseudotyped virus was ±2.4 times higher than that of the S-D614 pseudovirus – suggesting that the D614G mutation can enhance viral infectivity.  Secondly, although the majority of sera (93%) from convalescent COVID-19 patients could neutralize either S-D614 and S-G614 pseudotyped viruses, 7% (3/41) were unable to neutralize the D614G mutation in spike, showing that this mutation can lead to loss of neutralizing antibody activity. Whether this might be translated to a wider loss of sensitivity in infected patients remains to be seen, but possibly represents an important mutation to be aware of in upcoming vaccine trials.

Journal Article: Hu et al., Pre-Print. The D614G mutation of SARS-CoV-2 spike protein enhances viral infectivity and decreases neutralization sensitivity to individual convalescent sera. MedRxiv.

Summary by Clive Gray

 

 
 
 
 
 
 
International Union of Immunological SocietiesUniversity of South AfricaInstitute of Infectious Disease and Molecular MedicineScience Education PrizesElizabeth Glazer Pediatric Aids Foundation