Can the names “chicken IgY “and “chicken IgG” be used interchangeably?
Chicken IgG and chicken IgY are two different names for the same antibody. IgY is called so as it is the main antibody in egg yolk (y is from yolk). Human IgG got its name in the 1950’s when it was possible to divide human plasma in three fractions: alpha, beta and gamma. Later it was discovered that there were also IgA, IgM, IgD and IgA in mammals. Chicken IgY has a different isoelectric point than human IgG and will not migrate in exactly the same fraction as human IgG. It has no DNA similarity with human IgG. If there is any similarities, chicken IgY is more closely related to IgA or IgE. It was suggested by several research groups that chicken IgG was not the correct term. They wanted a name that showed that the antibody was different from human IgG and they thus called it IgY. The problem with the name IgY is that most users are working with mammalian antibodies due to tradition. When they start using chicken antibodies they assume that the antibody also is IgG and ask for chicken
