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Related to alloantigen: alloantibody, autoantigen, isoantigen, heterophile antigen, heteroantigen, xenoantigen
An antigen that occurs in some but not all members of the same species. Used by the immune system to distinguish self from nonself.
alloantigen/al·lo·an·ti·gen/ (-an´tĭ-jen) an antigen present in allelic forms encoded at the same gene locus in different individuals of the same species.
alloantigenAn antigen that occurs in some members of a species, which in humans is determined in part by the major histocompatibility complex.
An antigen that occurs in some, but not in other members of the same species. The term isoantigen is sometimes used in this sense.
an antigen existing in alternative (allelic) forms in a species, thus inducing an immune response when one form is transferred to members of the species who lack it; typical alloantigens are the blood group antigens.
canine secretory alloantigen system (CSA)
a minor histocompatibility system in dogs.