A Rapid and Simple Method for Screening Mixed Antigens as Candidates for a Multiantigen DNA Vaccine against the Poultry Red Mite (Dermanyssus gallinae)

The poultry red mite (PRM), Dermanyssus gallinae, is a major blood-feeding parasite in chickens.These parasites have developed resistance to certain commercial acaricides.Vaccination, which induces antibodies in chicken blood to interfere with the PRM's biological functions upon feeding, could be a promising alternative for controlling PRM, particularly a multi-antigen vaccine.However, simultaneously evaluating multiple antigen candidates requires many chickens, making the process costly and time-consuming.To address this, we proposed a rapid, simple, and animal-friendly method.This approach involved the rapid production of antigens as a DNA vaccine, followed by administration to egg-laying chickens for antibody production.The antibodies, immunoglobulin Y (IgY), were conveniently obtained from egg yolks.Since vaccine efficacy depends on antibody function, the IgYs were systematically combined into various formulations using an experimental design method, namely fractional factorial design.These combined IgYs were then fed to PRMs via in vitro feeding assays, enabling the assessment of a wide range of IgY formulations.Five potential PRM antigens, Cathepsin D-1, Protein of Unknown Function 1 (PUF-1), Akirin, Serpin (SRP-1), and Histamine Release Factor (HRF), were used as models for the method.Mite survival was monitored for 120 hours, and survival times were analyzed using Kaplan-Meier curves with log-rank tests and fractional factorial design statistical analysis.Key IgYs that significantly impacted PRM survival, such as PUF-1 and SRP-1, as well as all IgY interactions, were identified.This led to the selection of optimal antigen formulations for further testing in chickens.With this rapid screening method, fewer chickens are required, thereby reducing overall time, labor, and costs.