Human leukocyte antigen donors

Transfusion-induced autoimmune disease has been a significant complication in the treatment of patients who require multiple platelet transfusions. Platelets and lymphocytes carry their own blood group system, ie, the human leukocyte antigen (HLA) system, and it can be difficult to find an HLA matched donor. A mismatched platelet transfusion does not induce immediate adverse reactions, but may cause the patient to become refractory to the HLA type of the transfused platelets. The next time platelets with an HLA type similar to that of the transfused platelets are transfused, they are rejected by the patient and thus have no clinical efficacy. Exposure to platelets originating from different donors is minimized by the use of apheresis platelets. One transfusable dose (unit) of apheresis platelets contains 3-5 x 10 platelets. An equal dose of platelets from whole blood donation requires platelets from six to eight units of whole blood. Furthermore, platelets can be donated every 10 days, versus 10 weeks for whole blood donations. 

Allogeneic hematopoietic stem cell transplantation is the only therapy that is curative. The best candidates are younger than 16 years of age, have severe complications, and have human leukocyte antigen-matched donors. Risks must be carefully considered and include mortality, graft rejection, and secondary malignancies. 

The clinical significance of human leukocyte antigen (HLA) allele compatibility in patients receiving a marrow transplant from serologically HLA-A, HLA-B, and HLA-DR matched unrelated donors Morishima, Y., Sasazuki, T., Inoko, H., Juji, T., Akaza, T., Yamamoto, K., Ishikawa, Y., Kato, S., Sao, H., Sakamaki, H., Kawa, K., Hamajima, N., Asano, S., Kodera, Y. (2002). Blood, 99 (11) 4200-4206. 

HLA human leukocyte antigen HSCT hematopoietic stem cell transplantation hyper-CVAD high-dose methotrexate and cytarabine alternating with fractionated cyclophosphamide plus vincristine, doxorubicin, and dexamethasone IBMTR International Bone Marrow Transplant Registry IL-2 interleukin-2 MDS myelodysplastic syndrome MLL mixed lineage leukemia MUD matched unrelated donor NCCN National Comprehensive Cancer Network NST nonmyeloablative stem cell transplant OS overall survival Ph+ Philadelphia chromosome PML promyelocytic leukemia (gene)... 

Human leukocyte antigen (HLA) mismatching of allogeneic donor-recipient pairs at either class I or class II loci correlates with the risk of graft failure, graft-versus-host dis-ease (GVHD), and survival. The ideal donor is one that is matched at HLA-A, -B, -C, and DRB1. 

Barker JN, Davies SM, DeEor TE, et al. Survival after transplantation of unrelated donor umbilical cord blood is comparable to that of human leukocyte antigen-matched-unrelated donor bone marrow results of a matched-pair analysis. Blood 2001 97 2957-2961. 

Human leukocyte antigen (HLA) A lymphocyte antigen used in laboratory tests to determine compatibility of donor and recipient tissues for transplants. 

Respiratory Transfusion-related acute lung injury (TRALI) can be a serious adverse event after transfusion of plasma that contains antibodies against the recipient s leukocytes, and is the most common cause of transfusion-related mortahty. About 90% of cases of TRALI are associated with human leukocyte antigen (HLA) antibodies from the donor [39, 40 ]. Two mechanisms of TRALI have been suggested (1) an antigen-antibody reaction leads to a series of events (2) neutrophils are primed and become activated [7 ]. 

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). 

There are several transplantation modalities, depending on the type of donor and the source of hematopoietic cells. In all cases, the donor has to be identical or very similar to the recipient in the major histocompatibility system of human leukocyte antigens (HLA). If the donor is an identical twin of the recipient the transplant is named syngeneic, whereas if the donor is another type of individual the denomination is allogeneic in the latter circumstance the donor maybe related or unrelated to the patient. Frequently, the patient acts as his own hematopoietic donor and the name for such an approach is autologous transplantation. In this situation, the transplanted cells have to be collected and cryopreserved before the administration of high-dose therapy. 

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