What is a xenograft: September 2010
**Core Concept**
A xenograft is a type of graft that involves transplanting living cells, tissues, or organs from one species to another. This can be done within the same species (isograft), but xenografts specifically involve a different species, often for medical or research purposes.
**Why the Correct Answer is Right**
Xenografts are used in various medical fields, including organ transplantation, tissue engineering, and regenerative medicine. The recipient's immune system may reject the xenograft due to differences in histocompatibility antigens, making immunosuppressive therapy necessary to prevent rejection. Xenografts can also be used to study disease mechanisms or develop new treatments, as seen in the use of animal models in biomedical research.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because isografts involve transplanting cells or tissues from one individual to another of the same species, not from a different species.
**Option B:** This option is incorrect because allografts involve transplanting cells or tissues from one individual to another of the same species, but not from a different species.
**Option C:** This option is incorrect because autografts involve transplanting cells or tissues from one part of the body to another within the same individual.
**Clinical Pearl / High-Yield Fact**
When considering xenografts, it is essential to understand the risks of immune rejection and the potential for transmission of zoonotic diseases from the donor animal to the recipient.
**Correct Answer: D. Xenograft. A graft of living cells, tissues, or organs from one species to another.**