Allotransplant (allo- meaning "other" in Greek) is the transplantationofcells, tissues, or organs to a recipient from a genetically non-identical donor of the same species.[1] The transplant is called an allograft, allogeneic transplant, or homograft. Most human tissue and organ transplants are allografts.
It is contrasted with autotransplantation (from one part of the body to another in the same person), syngenic transplantation of isografts (grafts transplanted between two genetically identical individuals) and xenotransplantation (from other species).
Allografts can be referred to as "homostatic" if they are biologically inert when transplanted, such as bone and cartilage.[2]
An immune response against an allograft or xenograft is termed rejection. An allogenic bone marrow transplant can result in an immune attack on the recipient, called graft-versus-host disease.
In the US, the Food and Drug Administration (FDA) has regulated human tissue intended for transplants since 1993. In order to ensure the quality of donor tissue and reduce contamination and disease transmission risks, three regulations addressing manufacturing activities associated with human cells, tissues, and cellular and tissue-based products (HCT/Ps) were promulgated in May 2005:
companies producing and distributing HCT/Ps must register with the FDA.
"Donor Eligibility" rule: prescribes criteria for donor eligibility.
"Current Good Tissue Practices" rule: oversees overall processing and distribution practices of each company.
Autograft, tissue transplanted from one site to another on the same patient. An autograft reduces the risk of rejection but requires a second surgery site, adding pain, risk and possible longer aftercare.
As with many operations, allotransplantation risks some side effects. A limiting factor in tissue allotransplantation for reconstructive surgery deals with the side effects of immunosuppression (metabolic disorders, malignancies, opportunistic infections) which is a predominant issue. The risk of transmitting infection is high.[3]
^(W. P. Longmire, J. National Cancer Institute14, 669: The term homostatic graft might be applied to inert tissues such as bone and cartilage when transferred from one individual to another of the same species; and the term homovital graft might be used in reference to grafts whose cells must continue to grow and reproduce for the graft to be effective after similar transplantation; H. Conway, The Bulletin of the Hong Kong Chinese Medical Association13, 43: These grafts persist however as homostatic grafts and are completely replaced by host tissues in time.)
