The chicken immunoglobulin IgY is the avian equivalent to mammal IgG. The presence of IgY is higher in egg yolk than in serum, so by immunizing hens you have access to a generous source of antibodies solely by collecting eggs.
Chickens are known to produce antibodies against conserved mammalian proteins and peptides much more efficiently than mammals (1). This makes the choice of chicken as host obvious when working with human protein antigens.
IgY has no hinge-region and therefore is does not cross-react with rheumatoid factors or other naturally occurring anti-Fc antibodies (2)
IgY does not bind to mammalian Fc receptors. This avoids unspecific binding to cells expressing such receptors (e.g., macrophages and dendritic cells).
IgY does not recognize staphylococcal protein A and streptococcal protein G.
IgY does not activate mammalian complement systems. (3)
1) Schade, R., Calzado, E. G., Sarmiento, R., Chacana, P. A., Porankiewicz-Asplund, J., & Terzolo, H. R. (2005). Chicken egg yolk antibodies (IgY-technology): a review of progress in production and use in research and human and veterinary medicine. Alternatives to Laboratory Animals, 33(2), 129-154.
2) Larsson, A., Karlsson-Parra, A., & Sjöquist, J. (1991). Use of chicken antibodies in enzyme immunoassays to avoid interference by rheumatoid factors. Clinical chemistry, 37(3), 411-414.
3) Gassmann, M., Thömmes, P., Weiser, T., & Hübscher, U. (1990). Efficient production of chicken egg yolk antibodies against a conserved mammalian protein. The FASEB Journal, 4(8), 2528-2532.
4) Ohta M, Hamako J, Yamamoto S, Hatta H, Kim M, Yamamoto T, Oka S, Mizuochi T., Matsuura F., 1991, Structures of asparagine-linked oligosaccharides from hen egg-yolk antibody (IgY). Occurrence of unusual glucosylated oligo-mannose type oligosaccharides in a mature glycoprotein. Glycoconj J. 8:400-13.
Chicken IgY has a higher molecular weight compared to mammal IgG due to an extra heavy chain constant domain. This domain contains additional oligosaccharide sidechains (4), allowing more labeling with your preferred antibody tags. This produces higher signals in your immuno-assay.
Secondary antibodies against chicken IgYs don’t cross-react with mammalian IgGs.
When using IgY as secondary antibody chicken IgYs can be used together with mouse and rabbit antibodies, without the possibility of cross-reactivity.
At Ovodan Biotech we have developed and perfected a technology for IgY purification from egg yolk. The result is a purity of 80% for the total IgY, and over 95% for affinity purified specific antibodies. Today, our facilities offers a capacity of 20 gram total IgY per day. And our technology is liniary scalable.
IgY can be purified from egg yolk, which means that you have access to a generous source of antibodies. However, purifying IgY from the yolk is challenging due to the high presence of lipids. This might have contributed to the slightly flattering reputation of chicken antibodies.
However, at Ovodan Biotech we have developed and perfected a technology for IgY purification from egg yolk. The result is a purity of 80% for the total IgY, and over 95% for affinity purified specific antibodies.
Today, our facilities offer a capacity of 20 gram total IgY per day. Without the use of harsh chemicals. And our technology is linearly scalable.
Most importantly, this one-step purification method does not involve bleeding, nor do we sacrifice the chickens.
We believe that animal welfare is just as important as the health of human beings.
