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see transplantation, medicaltransplantation, medical,
surgical procedure by which a tissue or organ is removed and replaced by a corresponding part, usually from another part of the body or from another individual.
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A term used to describe the genes that influence acceptance or rejection of grafts. When grafts of tissue are exchanged between genetically dissimilar individuals, profound immunological rejection generally takes place. In contrast, grafts between genetically similar individuals, such as identical twins, are normally tolerated; they are histocompatible. Most known examples of histocompatibility (or H) genes encode polymorphic (that is, tending to differ between individuals) cell-surface proteins.

The major histocompatibility complex (MHC) contains a set of histocompatibility genes, termed major because mismatching at these genes invokes rapid rejection. The main function of MHC genes involves distinguishing self from nonself in the immune system, as part of preventing the spread of infectious disease. The body employs special mechanisms to avoid rejection of the fetus, which is effectively an allograft, that is, a graft from a donor to a genetically dissimilar recipient of the same species; in this case, the mechanisms include a diminution of MHC gene expression.

The MHC contains a spectrum of genes, many of which influence processing and presentation of antigens to the immune system. In mice, the MHC is designated the H-2 complex; in humans, it is referred to as the HLA complex (for human leukocyte A system). Mice and other mammals seem to have a similar arrangement of genes in their MHCs. See Antigen, Cellular immunology, Mendelism, Transplantation biology


The capacity to accept or reject a tissue graft.
References in periodicals archive ?
The major histocompatibility complex (MHC) encodes the cellular glycoproteins responsible for presenting self or non-self antigens to T cell receptors (TCR), and thereby initiate immune responses in invertebrates (Rothbard et al.
The study is not the first to implicate the major histocompatibility complex (MHC), a cluster of genes critical to the recognition of the body's own cells as "self," but it is the largest and most definitive, and its findings call into question data from smaller studies that suggested critical roles for other genetic regions.
Now the science bit - on the one hand, the bird's super-sniffer is searching for blokes with a Major Histocompatibility Complex that exudes a similar niff to her own, like.
Macrophages have a specialized set of molecules, called MHC-II (which stands for class II major histocompatibility complex).
After several medical evaluations, physicians discovered Lawrence had an immune deficiency disease called Major Histocompatibility Complex Class II deficiency.
Histocompatibility testing and matching between transplant organ and recipient is not performed for lung transplants as it is for other transplanted organs, such as the kidneys.
According to Marti Bailey, the American Society of Histocompatibility and Immunogenetics offers the ASHI Outstanding Technologist Award (OTA).
Electronic auction: provision of services for experimental quantification of binding of candidate peptides to alleles of i histocompatibility complex