Sex, age, and hospitalization drive antibody responses in a COVID-19 convalescent plasma donor population

Abstract

Conflict of interest: EMB reports receiving personal fees and nonfinancial support from Terumo BCT and personal fees and nonfinancial support from Grifols Diagnostic Solutions. EMB is a member of the United States FDA Blood Products Advisory Committee. Any views or opinions that are expressed in this manuscript are those of the authors, based on their own scientific expertise and professional judgment; they do not necessarily represent the views of either the Blood Products Advisory Committee or the formal position of the FDA, and also do not bind or otherwise obligate or commit either the advisory committee or the agency to the views expressed.

Convalescent plasma anti–SARS-CoV-2 spike protein ectodomain and receptor-binding domain IgG correlate with virus neutralization

“…The list of emergency-use authorized antibody testing platforms is rapidly expanding, and test performance, especially as it relates to VN, will be important to understand (32). Regardless, our findings are in agreement with a more recent report, which found that strong antivirus antibody responses were associated with male sex, older age, and hospitalization (33).…”

“…RT-PCR resting for SARS-CoV-2 infection. Symptomatic patients with a high degree of suspicion for COVID-19 disease were tested at the Molecular Diagnostics Laboratory at Houston Methodist Hospital using an assay filed for under Emergency Use Authorization from the US FDA (33). The assay follows the protocol published by the World Health Organization (35) and uses a 7500 Fast Dx instrument (Applied Biosystems) and 7500 SDS software (Applied Biosystems).…”

Convalescent plasma treatment of severe COVID-19: a propensity score–matched control study

“…3b) and in a larger cohort of individuals screened for serum antibodies within our health system 25 . Others have reported similar findings [26][27][28] . We did not observe a correlation between donor serum neutralizing titers and convalescent plasma-recipient outcomes (Fig.…”

The serological response to SARS corona virus-2 is characterized by frequent incomplete maturation of functional affinity (avidity)

“…These data confirm that the immune response towards SARS CoV-2 proteins shows an initial rise in avidity, reaching varying low to intermediate values, followed by cessation of further continuation of avidity maturation. A general low avidity of IgG towards SARS CoV-2 proteins has also been reported by other groups (13,14,33,34) though these authors did not recognize the specific kinetics of avidity maturation with its initial onset, followed by abrogation of maturation. Figure 3 illustrates the abrogation of avidity maturation in a characteristic case.…”

“…As a consequence, protection towards reinfection at a later time point is likely to be more efficient. The findings of a strict correlation between neutralizing potential of IgG directed towards SARS CoV-2 S1 protein/RBD and its avidity (33,34) is supporting this idea, though the overall avidity did not reach high values.…”