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Graft-versus-host disease

An incompatibility reaction (which may be fatal) in a subject (host) of low immunological competence (deficient lymphoid tissue) who has been the recipient of immunologically competent lymphoid tissue from a donor who lacks at least one antigen possessed by the recipient host; the reaction, or disease, is the result of action of the transplanted cells against those host tissues that possess the antigen not possessed by the donor. Seen most commonly following bone ma...

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