Foreignness of molecule that forms substance antigen

Question

Describe briefly the foreignness of the molecule that forms the substance antigenic.

Answer 1

To be antigenic macromolecules should come from the foreign source. Antigens from the related species are less antigenic in comparison to that of the unrelated species. More distance among the antigen sources the better is the antigenesity.

For example: Plant proteins are good antigens within the animals, however the duck serum proteins are not good antigens for chick.