Cross-Reactivity of Antibodies in Intravenous Immunoglobulin Preparation for Protection against SARS-CoV-2

• Published in: Microorganisms Vol. 11; no. 2; p. 471
• Main Authors: Osaka, Toshifumi, Yamamoto, Yoko, Soma, Takehisa, Yanagisawa, Naoko, Nagata, Satoru
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 13.02.2023; MDPI
• Subjects: ACE2; Angiotensin-converting enzyme 2; Antibodies; antibody-dependent enhancement; Antigens; Biology (General); blood; Cellulose acetate; Coronaviruses; COVID-19; COVID-19 infection; COVID-19 vaccines; cross reaction; Cross reactions (Immunology); cross-reactive antibody; Cross-reactivity; Dosage and administration; Enzymes; Guillain-Barre syndrome; health care workers; humans; immunoglobulin; Immunoglobulin G; Immunoglobulins; Immunological research; Infections; Infectious diseases; Intravenous administration; intravenous injection; labor; Low concentrations; Medical personnel; Pandemics; Pneumonia; Proteins; Pseudovirus; pseudovirus entry assay; QH301-705.5; SARS-CoV-2; Severe acute respiratory syndrome coronavirus 2; Spike protein; Testing; Vaccine development; Viral diseases; viruses; Japan; United Kingdom > UK; United States > US; cross-reactive antibody; pseudovirus entry assay; SARS-CoV-2; immunoglobulin; antibody-dependent enhancement
• ISSN: 2076-2607; 2076-2607
• DOI: 10.3390/microorganisms11020471

Severe cases of COVID-19 continue to put pressure on medical operations by prolonging hospitalization, occupying intensive care beds, and forcing medical personnel to undergo harsh labor. The eradication of SARS-CoV-2 through vaccine development has yet to be achieved, mainly due to the appearance of multiple mutant-incorporating strains. The present study explored the utility of human intravenous immunoglobulin (IVIG) preparations in suppressing the aggravation of any COVID-19 infection using a SARS-CoV-2 pseudovirus assay. Our study revealed the existence of IgG antibodies in human IVIG preparations, which recognized the spike protein of SARS-CoV-2. Remarkably, the pretreatment of ACE2/TMPRSS2-expressing host cells (HEK293T cells) with IVIG preparations (10 mg/mL) inhibited approximately 40% entry of SARS-CoV-2 pseudovirus even at extremely low concentrations of IgG (0.16–1.25 mg/mL). In contrast, the antibody-dependent enhancement of viral entry was confirmed when SARS-CoV-2 pseudovirus was treated with some products at an IgG concentration of 10 mg/mL. Our data suggest that IVIG may contribute to therapy for COVID-19, including for cases caused by SARS-CoV-2 variants, since IVIG binds not only to the spike proteins of the virus, but also to human ACE2/TMPRSS2. An even better preventive effect can be expected with blood collected after the start of the COVID-19 pandemic.