COVID-19 convalescent plasma donors: Unique motivations in unique times?

BACKGROUND: Early in the SARS-CoV-2 pandemic, many blood collection organizations (BCOs) were asked to collect and distribute COVID-19 convalescent plasma (CCP) as a potential treatment for this new virus and resulting disease. However, recruiting CCP donors presented unique challenges for BCOs, as there were few recovered patients at this time, and like the general population, most potential CCP donors had no blood donation experience. Thus, many CCP donors were new donors, and their donation motivations were unknown. MATERIALS AND METHODS: Donors who gave CCP at least once between April 27th and September 15th, 2020, were emailed a link to an online survey regarding their experience with COVID-19 and their motivations for donating CCP and blood. RESULTS: Of the 14,225 invitations sent, 3471 donors responded (24.4%). Most donors had never donated blood before (n = 1406), followed by lapsed donors (n = 1050), and recent donors (n = 951). There was a significant relationship between self-reported donation experience and fear of CCP donation (X2  = 119.2, p < .001). Motivations ranked "very important" by responding donors were wanting to help someone in need, a feeling of responsibility, and feeling a duty to donate. Donors with more severe disease were more likely to respond with feelings of a sense of duty to donate CCP (Χ2  = 8.078, p = .044) or altruism (Χ2  = 8.580, p = .035). CONCLUSIONS: Overwhelmingly, altruism and a sense of duty and responsibility were the reasons that CCP donors decided to donate. These insights can be useful for motivating donors for specialized donation programs or if wide scale CCP recruitment is needed in the future.

Anti-SARS-CoV-2 IgG and IgA antibodies in COVID-19 convalescent plasma do not enhance viral infection.

The novel coronavirus, SARS-CoV-2 that causes COVID-19 has resulted in the death of nearly 4 million people within the last 18 months. While preventive vaccination, and monoclonal antibody therapies have been rapidly developed and deployed, early in the pandemic the use of COVID-19 convalescent plasma (CCP) was a common means of passive immunization with a theoretical risk of antibody-dependent enhancement (ADE) of viral infection. Though vaccines elicit a strong and protective immune response and transfusion of CCP with high titers of neutralization activity are correlated with better clinical outcomes, the question of whether antibodies in CCP can enhance infection of SARS-CoV-2 has not been directly addressed. In this study, we analyzed for and observed passive transfer of neutralization activity with CCP transfusion. Furthermore, to specifically understand if antibodies against the spike protein (S) enhance infection, we measured the anti-S IgG, IgA, and IgM responses and adapted retroviral-pseudotypes to measure virus neutralization with target cells expressing the ACE2 virus receptor and the Fc alpha receptor (FcαR) or Fc gamma receptor IIA (FcγRIIA). Whereas neutralizing activity of CCP correlated best with higher titers of anti-S IgG antibodies, the neutralizing titer was not affected when Fc receptors were present on target cells. These observations support the absence of antibody-dependent enhancement of infection (ADE) by IgG and IgA isotypes found in CCP. The results presented, therefore, not only supports the therapeutic use of currently available antibody-based treatment, including the continuation of CCP transfusion strategies, but also the use of various vaccine platforms in a prophylactic approach.