1/11 Analysis of humoral immune response in #COVID19 patients provides key insights for #ConvalescentPlasma therapy and #Vaccine research: https://www.medrxiv.org/content/10.1101/2020.03.30.20047365v1">https://www.medrxiv.org/content/1...
2/11 A pseudotyped-lentiviral-vector-based neutralization assay was used to measure SARS-CoV-2-specific neutralizing antibodies (NAbs) in plasma from recovered COVID-19 patients with mild symptoms
3/11 ~30% of COVID19-recovered patients failed to develop high titers of neutralizing antibodies despite similar disease duration, suggesting key role of T-cells or cytokines in immune response
6/11 Neutralizing antibody titers of COVID-19 patients collected two weeks post-discharge did not significantly differ from those collected at the time of discharge
10/11 Limitations:
-Current lack of peer review (pre-print)
-Lack of information about the kinetics of viral loads (lacked respiratory specimens)
-Patients in severe and critical condition were excluded from the study (received passive antibody treatment before sample collection)
-Current lack of peer review (pre-print)
-Lack of information about the kinetics of viral loads (lacked respiratory specimens)
-Patients in severe and critical condition were excluded from the study (received passive antibody treatment before sample collection)
11/11 Concerns, commentary, and questions welcomed at this crucial stage of the #ConvalescentPlasma therapy effort @CCPP19 @ACasadevall1 @AlexAndersonMD @DrMJoyner @cshperspectives @VPrasadMDMPH @vincentRK @medrxivpreprint #coronavirus
4/11 Older COVID19-recovered patients demonstrated higher titers of both neutralizing and spike-binding #SARSCoV2-specific #antibodies
5/11 Temporal analysis of COVID19 antibody titers shows humoral immune response ramping up on day 10-15 post-onset of disease
7/11 NAb titers in ten of the 175 recovered patients were below limit of detection despite lab-confirmed infection with SARS-CoV-2
9/11 Despite 77.2% identical amino acids between SARS-CoV-2 and SARS-CoV spike proteins and cross-binding potential, COVID-19 convalescent plasma did NOT neturalize SARS-CoV, suggesting differences between #SARSCoV2 and #SARSCoV #epitopes and #immunogenicity