No SARS-CoV-2 Neutralization by Intravenous Immunoglobulins Produced From Plasma Collected Before the 2020 Pandemic

Abstract

The 2020 SARS-CoV-2 pandemic is caused by a zoonotic coronavirus transmitted to humans, similar to earlier events. Whether the other, seasonally circulating coronaviruses induce cross-reactive, potentially even cross-neutralizing, antibodies to the new species in humans is unclear. The question is particularly relevant for people with immune deficiencies, as their health depends on treatment with immunoglobulin preparations that need to contain neutralizing antibodies against the pathogens in their environment. Testing 54 intravenous immunoglobulin preparations, produced from plasma collected in Europe and the United States, confirmed highly potent neutralization of a seasonal coronavirus; however, no cross-neutralization of the new SARS-CoV-2 was seen.

Keywords: COVID-19; SARS coronavirus 2 antibody titer; SARS-CoV-2; intravenous immunoglobulin; neutralizing antibodies; plasma; primary immunodeficiency.

Figure 1.

Coronavirus neutralizing antibody titers in IVIG lots (n = 54) against (A) SARS-CoV-2 and (B) HCoV-229E. The IVIG lots were manufactured from plasma either donated by plasmapheresis (S), or recovered from whole blood donations (R), in the United States or central Europe. Each dot represents the mean of 2 independent experiments, except in (B) from 1 EU-R IVIG lot the titer of a single determination is shown. The lines represent the median in each group. Paired t tests were used for determination of significance. Abbreviation: EU, Europe; HCoV, human coronavirus; IVIG, intravenous immunoglobulin; LOD, limit of detection; µNT₅₀, 50% neutralization titer; R, recovered; S, source; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.