Development of a chicken-derived antivenom against the taipan snake (Oxyuranus scutellatus) venom and comparison with an equine antivenom.

Researchers worked on an antivenom developed from chickens for the taipan snake venom and compared its efficiency to that of a traditionally produced horse-based antivenom.

Procedure of Developing Chicken-Derived Antivenom

• The researchers started by generating a chicken-derived antivenom (ChDAv) specifically for the taipan snake (Oxyuranus scutellatus) venom.
• To create this, they extracted the anti-taipan IgY from egg yolks of hens that were previously immunized with taipan venom.

Comparison between Chicken-Derived and Horse-Based Antivenom

• The team then compared the ChDAv with a horse-based antivenom (EDAv) in multiple aspects including productivity, ability to neutralize venom, pharmacokinetic properties, anti-venomous profile, and immunogenicity.
• They discovered that to match the mass of anti-taipan antibodies produced in one liter of horse hyperimmune plasma, they needed to collect and process the yolk of 382 chicken eggs.
• To generate the same amount of anti-taipan antibodies produced by a single horse in a year, 63 chickens were needed.

Cost and Efficiency of Chicken-Derived Antivenom

• From the study, it was estimated that producing anti-taipan antibodies could be 40% cheaper in Costa Rica if chickens were used as the source of immunoglobulins (IgY), instead of horses.
• However, when assessing ChDAv’s venom neutralization abilities, it exhibited a weaker ability to counteract the alpha subunit of taipoxin, a primary neurotoxin in the taipan venom, in contrast to EDAv.
• Further, ChDAv exhibited reduced ability to neutralize coagulant and lethal activities of taipan venom.

Pharmacokinetics and Immunogenicity

• ChDAv was found to be more immunogenic in rabbits than EDAv, suggesting that the immunogenic response could be more pronounced due to chickens being phylogenetically more distant to rabbits than horses.
• This finding may explain the faster clearance from rabbit bloodstream of chicken-IgY as compared to equine-IgG observed in the pharmacokinetic study.

Conclusion of the Study

• The researchers concluded that the production of anti-taipan antivenom was less effective when using chicken egg yolks as a source of immunoglobulins compared to horses, despite potential cost advantages.