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A protein or other substance, such as histocompatibility or red blood cell antigens, that is present in only some members of a species and therefore able to stimulate isoantibody production in other members of the same species who lack it. Also called alloantigen.

i′so·an′ti·gen′ic (-jĕn′ĭk) adj.
i′so·an′ti·ge·nic′i·ty (-jə-nĭs′ĭ-tē) n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Physiology) immunol relating to an isoantigen or isoantigens
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