International Journal of Health Sciences

Determination of SARS-CoV-2 Spike Protein Epitopes Recognized by Pooled IgGs from COVID-19 Plasma
Qinfeng Liu, Meghana Reddy Gogireddy, Asif Zia

Abstract
COVID-19 has brought an unprecedented health crisis around the world. This study aimed to reveal peptide epitopes on the SARS-CoV-2 spike antigen targeted by IgGs in COVID-19 convalescent and vaccine plasma to better understand immune responses to COVID-19 infection and vaccination. Peptide epitopes were isolated at picogram level by passing a synthetic peptide library mixture of SARS-CoV-2 spike protein through columns with immobilized IgGs isolated from blood donated by COVID-19 convalescent and vaccinated individuals in a rural community. Multiple spike antigen peptide epitopes were identified by mass spectrometry based proteomic analysis and about two thirds of the epitopes had specific binding with both the convalescent IgGs and the vaccine IgGs. The 3D mapping of the epitopes demonstrated polyclonal nature of COVID-19 IgGs which recognized broad regions of the SARS-CoV-2 spike antigen.

Full Text: PDF     DOI: 10.15640/ijhs.v9n3a3