Accession Number:

AD1105910

Title:

Relationship between Anti-Spike Protein Antibody Titers and SARS-CoV-2 In Vitro Virus Neutralization in Convalescent Plasma

Descriptive Note:

Journal Article - Open Access

Corporate Author:

ARMY MEDICAL RESEARCH INST OF INFECTIOUS DISEASES FORT DETRICK MD FORT DETRICK

Report Date:

2020-06-09

Pagination or Media Count:

35.0

Abstract:

Newly emerged pathogens such as SARS-CoV-2 highlight the urgent need for assays that detect levels of neutralizing antibodies that may be protective. We studied the relationship between anti-spike ectodomain ECD and anti-receptor binding domain RBD IgG titers, andSARS-CoV-2 virus neutralization VN titers generated by two different in vitro assays using convalescent plasma samples obtained from 68 COVID-19 patients, including 13 who donated plasma multiple times. Only 23 1668 of donors had been hospitalized. We also studied 16samples from subjects found to have anti-spike protein IgG during surveillance screening of asymptomatic individuals. We report a strong positive correlation between both plasma anti-RBD and anti-ECD IgG titers, and in vitro VN titer. Anti-RBD plasma IgG correlated slightly better than anti-ECD IgG titer with VN titer. The probability of a VN titer 160 was 80 or greater with anti-RBD or anti-ECD titers of 11350. Thirty-seven percent 2568 of convalescent plasma donors lacked VN titers 160, the FDA-recommended level for convalescent plasma used for COVID-19 treatment. Dyspnea, hospitalization, and disease severity were significantly associated with higher VN titer. Frequent donation of convalescent plasma did not significantly decrease either VN or IgG titers. Analysis of 2,814 asymptomatic adults found 27 individuals with anti-RBD or anti-ECD IgG titers of 11350, and evidence of VN1160. Taken together, we conclude that anti-RBD or anti-ECD IgG titers can serve as a surrogate for VN titers to identify suitable plasma donors. Plasma anti-RBD or anti-ECD titer of11350 may provide critical information about protection against COVID-19 disease.

Subject Categories:

  • Medicine and Medical Research

Distribution Statement:

APPROVED FOR PUBLIC RELEASE