Canine distemper virus (CDV)-neutralizing activities of an anti-CDV canine-derived single-chain variable antibody fragment 4-15 (scFv 4-15) screened by phage display technology

• Published in: International journal of biological macromolecules 2024-02, Vol.257 (Pt 2), p.128645-128645, Article 128645
• Main Authors: Li, Yuan, Song, Jingge, Jiang, Sheng, Yang, Yaqi, Han, Yanyan, Zhong, Linhan, Zhou, Jiaying, Wang, Mei, Song, Houhui, Xu, Yigang
• Format: Article
• Language: English
• ISSN: 0141-8130; 1879-0003
• DOI: 10.1016/j.ijbiomac.2023.128645

Canine distemper virus (CDV) is a highly contagious pathogen that causes severe diarrhea, fever and vomiting in domestic dogs, posing a serious threat to the dog breeding industry. Currently, there are no effective therapeutic agents for emergency treatment despite the availability of vaccines against CDV infection. Single-chain fragment variable (scFv) antibody has been demonstrated to effectively inhibit virus infections, suggesting a potential candidate as a therapeutic agent for canine distemper. In this study, a phage-displayed scFv library was constructed from the peripheral blood lymphocytes of dog immunized intramuscularly with live-attenuated CDV vaccine, and was subjected to four rounds of pannings against CDV. Subsequent indirect enzyme-linked immunosorbent assay screening revealed high-affinity scFv antibodies specific to CDV, and indirect immunofluorescence assay screening revealed CDV-neutralizing activity of scFv antibodies. Our results showed that a scFv antibody 4-15 (scFv 4-15) with high-affinity binding to CDV and neutralizing activity against CDV was obtained, which displayed effective therapeutic potential in vivo for dogs challenged with a lethal dose of CDV. Conclusively, the scFv 4-15 with high-affinity binding and neutralizing activity to CDV that was obtained by phage display technology provides a promising candidate for the therapeutic agents against CDV infection.