Histocompatibility 144757 223529568 2008-07-04T13:46:49Z KC Panchal 3449833 /* See also */ expanded {{unreferenced|date=April 2007}} '''Histocompatibility''' is the property of having the same, or mostly the same, [[allele]]s of a set of [[gene]]s called the [[major histocompatibility complex]]. These genes are expressed in most tissues as [[antigen]]s, to which the [[immune system]] makes [[antibody|antibodies]]. The immune system at first makes antibodies to all sorts of antigens, including those it has never been exposed to, but stops making them to antigens present in the body. If the body is exposed to foreign antigens, as by getting a tissue [[medical grafting|graft]], it attacks the foreign material unless it is histocompatible. A similar system exists in many [[plant]]s; its purpose is not to reject grafts, but to prevent [[inbreeding]]. Pollen from a plant sharing a histocompatibility gene with the female either fails to grow or dies soon after germinating. ==See also== * [[Transplant rejection]] * [[Tissue typing]] * [[Major histocompatibility complex]] * [[Clonal selection theory]] ==External links== * {{MeshName|Histocompatibility}} * {{eMedicineDictionary|Histocompatibility}} [[Category:Pollination]] [[Category:Immune system]] [[fr:Histocompatibilité]]