Poster Presentation International Veterinary Immunology Symposium 2016

Production and Characterization of Neutralizing Antibodies against Bungarus multicinctus Snake Venom (#171)

Yi-Yuan Yang 1 , Chi-Hsin Lee 1 , Yu-Ching Lee 1 , Liang-Tzung Lin 1 , Jen-Ron Chiang 2 , Sy-Jye Leu 1
  1. Taipei Medical University, Taipei, TAIPEI, Taiwan
  2. Center for Research, Diagnostics and Vaccine Development, Centers for Disease Control, , Ministry of Health and Welfare, Taipei, Taiwan

The bite of the venomous snake, the banded krait (Bungarus multicinctus; BM), contains neurotoxic venom proteins (BM proteins) and is one of the major envenomation species in the world including Taiwan. Even though horse-derived serum has efficacy as therapy against snake venom, it has high costs and side effects, so alternative cost-effective and safe techniques need to be developed. In this study, chickens were immunized with glutaraldehyde-attenuated BM proteins using, and polyclonal immunoglobulin Y (IgY) antibodies were purified from eggs. IgY showed a similar binding activity to BM proteins as horse antivenin on Western blot, and the titer in chickens lasted for at least 6 months as assayed by an ELISA assay. We constructed two antibody libraries by phage display technology containing 1.0 ×107 and 2.9 × 108 transformants, respectively. After four rounds of bio-panning, eluted phage titers and phage-based ELISA indicated specific clones were enriched. Thirty randomly selected expressing monoclonal single-chain variable-fragment (scFv) antibodies were classified into four groups with a short linker and two groups with a long linker. These selected scFv antibodies showed specificity and different binding activities to BM proteins but not to venomous proteins of other snakes commonly present in Taiwan. Their binding specificity was further confirmed by competitive ELISA. Most importantly, polyclonal IgY demonstrated a similar neutralization efficiency against BM proteins as did horse-derived antivenin in mice injected with a minimum lethal dosage (MLD) of venom proteins. A mixture of several monoclonal anti-BM scFv antibodies were also able to partially inhibit the lethal effect on mice to increase the survival time and rate. We profoundly believe that the IgY and scFv antibodies can be applied in developing diagnostic agents for wound exudates and as an alternative treatments for snakebite envenomations in the future.