Human leukocyte antigen tissue typing

Laboratory assessment includes indicators of general operative health (e.g., electrolytes, acid-base status, clotting profile, full blood cell count, and cross-matching). In addition, full human leukocyte antigen (HLA) tissue typing is undertaken, in addition to a full screen for infectious diseases, particularly cytomegalovirus (CMV), hepatitis, herpes, and HIV status, as these infections can be activated by immunosuppressive therapy. 

Tissue type is determined hy molecules on the surface of every cell in the body. These molecules are called human leukocyte antigens (HLA) or the major histocompatibility complex (Petersdorfet et al. 1998 Villard 2006). Each person has unique HLAs. The HL As on the cells of the transplant signal to the body that this tissue is foreign, when a person receives a transplant, and stimulate an immune response. The recipient s blood usually is screened for antibodies against the tissues of the specific potential donor. If these antibodies are present severe rejection is expected, and transplantation will not be performed in these cases (Matas and Schnitzler 2004 Talbot and Manas 1997). 

Classification Human interferons have been classified into three type s, a, p, and y, on the basis of their antigenicity. The a interferons are primarily leukocytic, whereas the p and y interferons are produced by connective tissue fibroblasts and T lymphocytes, respectively. Recombinant DNA techniques in bacteria have made available large quantities of a interferon/species A—designated a2(A) interferon—which has the advantage of being purer than previous preparations derived from leukocytes. Currently the other interferons have also been obtained by recombinant techniques. 

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