Studies on beta-lactoglobulin as an experimental allergen in rats

The allergenicity of bovine beta-lactoglobulin (beta-LG) in rats was investigated by measurement of both mast cell-bound and circulating IgE antibody produced in response to immunisation with this cow's milk constituent. The responsiveness of the animals' peritoneal mast cells to in vitro challenge with beta-LG was determined by measurement of release of radiolabelled 5-hydroxytryptamine. Using aluminium hydroxide gel as adjuvant, the responsiveness of mast cells to beta-LG was transient, peaking at 21 days after immunisation. The optimal dose of injected beta-LG was 100 micrograms. Circulating IgE antibody to beta-LG, measured by ELISA, was also detected transiently during the 3rd week post-immunisation.