Immunisation against Human Leucocyte Antigens (HLA) can be caused by pregnancy, blood transfusion, or organ transplants. The HLA antibody status of a given patient significantly influences their access and waiting time to transplant. For some highly sensitised patients (HSP) there is hardly any suitable donor available in the deceased donor pool of their allocation organisation and therefore they wait a very long time before being offered a kidney for transplant. Especially patients with rare HLA phenotypes in relation to the actual donor pool are waiting extremely long. As HLA phenotypes are different in the various European populations, we hypothesized that extension of the donor pool outside the respective allocation system will increase the chance of receiving a compatible transplant for this subgroup of highly sensitised patients. One of the objectives of the EUROSTAM project, (a Europe-wide Strategy to enhance Transplantation of highly sensitised patients on the basis of Acceptable HLA Mismatches) was to develop a tool to compare the chance of transplanting HSP in different European populations with donor organs from within and outside their own donor pool.

Information on the HLA type and ABO blood group of the actual donor population, as well as the acceptable mismatches of long waiting HSP were obtained from the EUROSTAM partner organizations i.e. Eurotransplant (ET), UK National Health Service Blood and Transplant (NHSBT), Barcelona, Prague and Athens.

Results from simulations using the newly developed tool shows that 195 (27%) of the 724 long waiting highly sensitised patients registered at each partner organisation have increased chances of transplant in a different European donor pool. This makes a strong case for sharing kidneys between European countries for selected difficult to transplant patients.

孕妇，输血或器官移植可引起针对人类白细胞抗原（HLA）的免疫接种。给定患者的HLA抗体状态会显着影响其获取和等待移植的时间。对于一些高度敏感的患者（HSP），在其分配机构已故的捐赠者库中几乎没有合适的捐赠者可用，因此，他们需要等待很长的时间才能接受肾脏移植。特别是相对于实际供体池而言，HLA表型稀少的患者等待时间非常长。由于欧洲不同人群的HLA表型不同，我们假设将供体库扩展到各自的分配系统之外将增加针对此高敏患者亚组接受相容性移植的机会。

有关实际供血人群的HLA类型和ABO血型的信息，以及长期等待的HSP的可接受的失配，可从EUROSTAM合作伙伴组织获得，例如，Eurotransplant（ET），英国国家卫生部门血液和移植（NHSBT），巴塞罗那，布拉格和雅典。

使用新开发的工具进行的模拟结果表明，在每个伙伴组织注册的724名等待时间长的高敏患者中，有195名（27％）在不同的欧洲捐助者库中进行移植的机会增加。这为在某些难以移植的患者中在欧洲国家之间共享肾脏提供了强有力的理由。