Frontiers in Microbiology (Nov 2020)

Prevalence of Severe Acute Respiratory Syndrome Coronavirus 2 Neutralizing Antibodies in Egyptian Convalescent Plasma Donors

  • Mokhtar R. Gomaa,
  • Ahmed Kandeil,
  • Ahmed Mostafa,
  • Wael H. Roshdy,
  • Ahmed E. Kayed,
  • Mahmoud Shehata,
  • Omnia Kutkat,
  • Yassmin Moatasim,
  • Ahmed El Taweel,
  • Sara H. Mahmoud,
  • Mina Nabil Kamel,
  • Noura M. Abo Shama,
  • Mohamed El Sayes,
  • Rabeh El-Shesheny,
  • Osama H. Bakheet,
  • Mohamed A. Elgohary,
  • Mohamed Elbadry,
  • Naguib N. Nassif,
  • Salwa H. Ahmed,
  • Ibrahim Y. Abdel Messih,
  • Ghazi Kayali,
  • Ghazi Kayali,
  • Mohamed A. Ali

DOI
https://doi.org/10.3389/fmicb.2020.596851
Journal volume & issue
Vol. 11

Abstract

Read online

Using convalescent plasma as immunotherapy is an old method for treatment of infectious diseases. Several countries have recently allowed the use of such therapy for the treatment of COVID-19 patients especially those who are critically ill. A similar program is currently being tested in Egypt. Here, we tested 227 plasma samples from convalescent donors in Egypt for neutralizing antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using a microneutralization (MN) assay. A third of the tested samples did not have antibody titers and 58% had titers between 1:10 and 1:80. Only 12% had titers >1:160. We also compared MN assays using different virus concentrations, plaque reduction neutralization (PRNT) assays, and a chemiluminescence assay that measures immunoglobulin G (IgG) binding to N and S proteins of SARS-CoV-2. Our results indicated that a MN assay using 100 TCID50/ml provides comparable results to PRNT and allows for high throughput testing.

Keywords