APPLICATION OF THE IMMUNE-COMPLEX FOR IMMUNE PROTECTION AGAINST VIRALDISEASE

An immune complex (IC), composed of antigenic subunits of the Newcastl e disease virus (NDV) and specific polyclonal allogeneic antibodies, w as used to protect chickens against NDV. Antibodies in the IC were chi cken immunoglobulin G. The antibody:antigen ratio in IC was 2.03. The IC was prepared at equivalence by direct mixing of NDV-infected allant oic fluid, treated with Triton X-100, and chicken anti-NDV serum. In o rder to bind NDV antigenic subunits to specific antibodies, previous i solation and purification of antigen is not required. Chickens were im munized with 1 mg IC, containing 0.3788 mg of viral antigens. The IC, prepared in the form of an oil-emulsion, was administered intramuscula rly. The IC generated high levels of anti-NDV antibodies and successfu lly protected chickens against live virus challenge. Therefore, the IC could be recommended as a safe and environmentally convenient vaccine .