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.
【저자키워드】 severe acute respiratory syndrome coronavirus 2, Neutralizing antibodies, Microneutralization assay, Egypt, plasma donors, 【초록키워드】 Treatment, convalescent plasma, neutralizing antibody, SARS-CoV-2, IgG, coronavirus, therapy, Diseases, S protein, Immunotherapy, Critically ill, Immunoglobulin, Antibody titer, convalescent, chemiluminescence, PRNT, Donor, binding, microneutralization, COVID-19 patient, Virus concentrations, acute respiratory syndrome, measure, plaque reduction neutralization, country, plasma sample, tested, indicated, assays, provide, comparable, 【제목키워드】 coronavirus 2, respiratory,