[Avian yolk antibodies in diagnosis and research]

Hens were immunized with bacterial polysaccharide (alginate), Hepatitis B surface antigen (HBsAg), and potato viruses (PVA, PVS, PVM, PVX, and PVY). The antibodies were isolated noninvasively from the yolks of laid eggs. The purified yolk immunoglobulins (IgY) were tested in an array of various assays and diagnostic techniques. The methods employed were precipitation reactions, immun-electrophoresis, ELISA (after biotinylation of IgY), immuno-gold electron microscopy, and western and immuno blotting. Some of these methods had to be modified according to the special requirements of avian antibodies. The special handling of this animal system is described in regard to antibody production. The results demonstrate that IgY derived from hens can replace IgG produced by traditional methods in mammals. The advantages of this alternate animal system are emphasized in respect to animal care, high productivity, and special suitability of avian antibodies for certain diagnostic purposes.