Work

Equine Hyperimmune Serum against the Inactivated SARS-CoV-2 Has Antibodies Neutralizing Titers

Year: 2025

Type: article

Abstract: The use of passive immunization could be a strategy for the control of SARS-CoV-2 infections. Our study proposes to produce anti-SARS-CoV-2 antibodies from the immunization of horses, and purify F(ab’)2 fragment aiming to provide a therapy capable of acting in the treatment of infections, prevention, and control of COVID-19 outbreaks. To produce hyperimmune sera animals were inoculated with SARS-CoV-2 inactivated viral particles added with Freund's or aluminum hydroxide as adjuvant. Antibodies level was determined by indirect ELISA using the inactivated SARS-CoV-2 virus. Independent of the adjuvant used, a specific antibody anti-SARS-CoV-2 were detected from the second inoculation up to 4 months. The presence of neutralizing antibodies was observed from the third dose and was maintained until day 110 of the experiment. The antibodies fragmentation process was able to produce F(ab’)2 fragments and maintained the antibody ability to recognize, bind and neutralize the antigen in vitro. To evaluate the safety and effect of antibodies in vivo, we transferred the equine F(ab’)2 antibodies to mice. Mice remained healthy and equine anti-SARS-CoV-2 antibodies were detected in sera. Anti-SARS-CoV-2 antibodies obtained are able to neutralize SARS-CoV-2 virus and are highlighted as a potential therapeutic option for the COVID-19 treatment.

Source: Brazilian Archives of Biology and Technology

DOI: 10.1590/1678-4324-2025230848