biostudies-literatureUnknown24(4)Xu MTherapeutic antibodies-F(ab')2 obtained from hyperimmune equine plasma could treat emerging infectious diseases rapidly because of their high neutralization activity and high output. However, the small-sized F(ab')2 is rapidly eliminated by blood circulation. This study explored PEGylation strategies to maximize the half-life of equine anti-SARS-CoV-2 specific F(ab')2. Equine anti-SARS-CoV-2 specific F(ab')2 were combined with 10 KDa MAL-PEG-MAL in optimum conditions. Specifically, there were two strategies: Fab-PEG and Fab-PEG-Fab, F(ab')2 bind to a PEG or two PEG, respectively. A single ion exchange chromatography step accomplished the purification of the products. Finally, the affinity and neutralizing activity was evaluated by ELISInternational journal of molecular sciences3387https://www.ebi.ac.uk/biostudies/studies/S-EPMC9963672biostudies-literaturePEGylation Prolongs the Half-Life of Equine Anti-SARS-CoV-2 Specific F(ab')2.PMC9963672Mo RFeng NXia XXu MWang TWang XYang SBi JZhao YLiang BYan FfalsePEGylation Prolongs the Half-Life of Equine Anti-SARS-CoV-2 Specific F(ab')2.Therapeutic antibodies-F(ab')2 obtained from hyperimmune equine plasma could treat emerging infectious diseases rapidly because of their high neutralization activity and high output. However, the small-sized F(ab')2 is rapidly eliminated by blood circulation. This study explored PEGylation strategies to maximize the half-life of equine anti-SARS-CoV-2 specific F(ab')2. Equine anti-SARS-CoV-2 specific F(ab')2 were combined with 10 KDa MAL-PEG-MAL in optimum conditions. Specifically, there were two strategies: Fab-PEG and Fab-PEG-Fab, F(ab')2 bind to a PEG or two PEG, respectively. A single ion exchange chromatography step accomplished the purification of the products. Finally, the affinity and neutralizing activity was evaluated by ELIS2023-01-01T00:00:00Z2023 Feb2025-04-21T14:37:00.016Z2025-04-21T14:37:00.016ZS-EPMC99636723683480310.3390/ijms24043387