With few drugs to combat SARS-CoV-2 infections and the approval from the U.S. FDA for Emergency Use Authorization of COVID-19 convalescent plasma (CCP), many patients are now receiving CCP. In order to gain a better understanding of the antiviral properties of CCP, researchers profiled 126 plasma samples from eligible convalescent donors using an Fc array assay customized for both variable Fv (variable) and Fc (constant) antibody domains against antigens from SARS-CoV-2 and other coronaviruses. Researches confirmed wide variability in the SARS-CoV-2 antibody response in terms of magnitude of response and antigens recognized. In addition to viral neutralization antibodies, CCP also contained antibodies to mediate complement activation, phagocytosis, and antibody-dependent cellular cytotoxicity against SARS-CoV-2. In a separate case study, doctors report success in treating SARS-CoV-2 in a nine-week-old female baby with trisomy 21. The infant had cardiopulmonary failure associated with COVID-19 and did not respond to remdesivir, but recovered after transfusion with two units of CCP. Future studies are required to fully understand the mechanism of clearing SARS-CoV-2, but other mechanisms beyond viral neutralization may be especially important for some patients.
References:
- Natarajan H, Crowley AR, Bulter SE, Xu S, et al. SARS-CoV-2 antibody signatures robustly predict diverse antiviral functions relevant for convalescent plasma therapy. MedRxIV
- Rodriguez Z, Shane AL, Verkerke H, Lough C, et al. COVID-19 convalescent plasma clears SARS-CoV-2 refractory to remdesivir in an infant with congenital heart disease. Blood Advances 2020; 4(18); 4278-4281
