Immune Tolerance To Allografts
There are many instance in which an allograft may be accepted without the use of immunosuppressive measure. Obviously, in the case of tissue that lack alloantigen, such as cartilage or heart valve, there is no immunological barrier to transplantation. However there are also instances in which the strong predicted response to an allograft does not occur. There are two general cases in which an allograft may be accepted. One is when cells or tissue are grafted to a so-called privileged site that is sequestered from immune surveillance. The second is when a state of tolerance has been induced biologically, usually by previous exposure to the antigen of the donor in a manner that cause immune tolerance rather than sensitization in the recipient.
Read more about this topic: Immune Tolerance
Famous quotes containing the words immune and/or tolerance:
“The moral immune system of this country has been weakened and attacked, and the AIDS virus is the perfect metaphor for it. The malignant neglect of the last twelve years has led to breakdown of our country’s immune system, environmentally, culturally, politically, spiritually and physically.”
—Barbra Streisand (b. 1942)
“Children who begin life with an eagerness to please, need to know that not pleasing is also all right now and then. They learn tolerance for others’ faults through our tolerance of their own.”
—Cathy Rindner Tempelsman (20th century)