Non-invasive Antibody Production in the Chicken

Sammanfattning: The production of antibodies for analytical purposes using invasive procedures on small mammals is common practice in biomedical research. The aim of this study was to develop an efficient method for non-invasive antibody production in the chicken. This thesis presents an alternative method that eliminates the discomfort, pain and distress invoked by traditional immunization procedures on mammals by instead harvesting antibodies (IgY) from the yolk of eggs laid by orally immunized hens.An efficient oral immunization regime was developed by first trying out a suitable non-aggressive oral adjuvant with Bovine Serum Albumine (BSA) as the model antigen. It was found that the pegylated mono/diglyceride RhinoVax® (Softigen®) at a concentration of 20% (v/v) produced a good humoral antibody response in chickens as well as development of IgY antibodies in the egg yolk. The age of the chicken is important in order to have a proper humoral immune response. We found that chicken older than 22 days produced circulating immunospecific anti BSA-antibodies of of IgG, IgM and IgA class when orally immunized with BSA alone, whereas chickens 15 days old only produced IgM and IgA antibodies.This is the first report of oral immunizations with a high dose (250–300mg) of BSA in 20% RhinoVax® consisting of 3 or 5 consecutive daily doses resulting in high concentrations of immunospecific IgY antibodies in the yolk. Using this technique of three consecutive daily doses repeated after 7 weeks and after 18 weeks, a booster effect was induced after the third immunization. This is the first demonstration of a clear anamnestic immune response in orally immunized chickens. The results suggest that it may be possible to further increase the concentration of immunospecific IgY antibodies by modifying the immunization regime. It seems plausible to develop a procedure where the immunogen can be fed to the chickens as in an ordinary egg producing farm thus making antibody production not classified as an animal experiment.