Antigenic Diversity of the Major Histocompatibility Complex among Recipients and Related Donors of Hematopoietic Stem Cells
The number of allogeneic hematopoietic stem cell transplants (allo-HSCT) performed annually around the world continues to grow. The advances in HLA typing, improved supportive therapy, and reduced intensity of conditioning regimens increase the number of allo-HSCTs. Assessment and testing of the donor before transplantation are very important processes that affect the quality and safety of donation. For unrelated hematopoietic stem cell (HSC) donors, the WMDA (World Bone Marrow Donor Organization), which fosters collaboration in clinical transplantation and promotes the interests of unrelated stem cell donors, has developed the standards for recruiting, counseling and working with potential HSC donors to protect donor interests. There are various strategies not only to attract more potential HSC donors, but also to increase the diversity of HLA phenotypes. The allele frequencies of the HLA system are specific for populations, which limits the number of different phenotypes that we obtain when typing new potential donors. Today, in order to ensure the safety and respect for the rights of related donors, the global trend is the recruitment and examination of this contingent on the base of bone marrow donor registries. The results of the survey are subsequently included in the information bases of potential HSC donors, which allows in the future, with the consent of the donor, to attract them for donation as an unrelated donor.