SARS-CoV-2 neutralization and serology testing of COVID-19 convalescent plasma from donors with non-severe disease

Abstract

We determined the antigen binding activity of convalescent plasma units from 47 individuals with a history of non-severe COVID-19 using three clinical diagnostic serology assays (Beckman, DiaSorin, and Roche) with different SARS-CoV-2 targets. We compared these results with functional neutralization activity using a fluorescent reporter strain of SARS-CoV-2 in a microwell assay. This revealed positive correlations of varying strength (Spearman r = 0.37-0.52) between binding and neutralization. Donors age 48-75 had the highest neutralization activity. Units in the highest tertile of binding activity for each assay were enriched (75-82%) for those with the highest levels of neutralization.

Comparative analysis of three laboratory based serological assays for SARS-CoV-2 in an Australian cohort

“…26 Other studies have demonstrated variable correlation between binding antibodies and neutralising antibodies, depending on severity of illness, but further evaluation is required. 27,28 In addition, the level of antibody required to result in protection is yet to be elucidated. Isolated reports of SARS-CoV-2 reinfection with genetically distinct strains have recently emerged.…”

Current advances in transfusion medicine 2020: A critical review of selected topics by the AABB Clinical Transfusion Medicine Committee

“…Numerous blood donor centers in the US implemented SARS-CoV-2 IgG antibody testing of blood donors in spring/summer 2020 to assist in the recruitment and collection of CCP. 11,[14][15][16][17][18][19][20] The FDA requires CCP to contain anti-SARS-CoV-2 antibodies; to ensure that the donors have sufficient antibodies, they must have had symptoms of COVID-19 and a positive test for COVID-19 or a reactive (positive) result in two different tests approved, cleared, or authorized by the FDA to detect SARS-CoV-2 antibodies. There is an additional recommendation to measure neutralizing antibody (nAb) titers if possible.…”

“…21 Published data report that 82%-93.5% of donors with prior SARS-CoV-2 infection have demonstrable IgG antibodies with a positive correlation detected between the level of SARS-CoV-2 IgG antibodies and nAb titers. [14][15][16][17][18][19][20] A time-dependent decline has been shown in both nAb titers and detectable IgG in CCP donors and the general population post-infection. This may impact the maximum time a recovered person may donate CCP and also has important implications for durability of immunity.…”

“…70 This phase 2b/3, double-blind trial randomized 347 Alzheimer's disease (AD) patients from 41 sites in the United States (22) and Spain (19). Subjects between 55 and 85 years of age with a probable diagnosis of mild-tomoderate AD (Mini-Mental State Examination [MMSE] score of [18][19][20][21][22][23][24][25][26] and receiving stable doses of acetylcholinesterase inhibitors and/or N-methyl-D-aspartate receptor antagonists were assigned to one of three TPE treatment groups with varying doses of albumin and intravenous immune globulin (IVIG) or a placebo group that included sham TPE. The primary endpoint assessed changes from baseline to 14 months in two measures: the AD Cooperative Study-Activities of Daily Living (ADCS-ADL) and the AD Assessment Scale-Cognitive Subscale (ADAS-Cog).…”