Cohen Yossi, Nagler Arnon
Institute of Hematology, Department of Bone Marrow Transplantation and Cord Blood Bank, Sheba Medical Center, Tel Hashomer, Israel.
Isr Med Assoc J. 2004 Jan;6(1):39-46.
In recent years, umbilical cord blood has emerged as an alternative source of hematopoietic progenitors (CD34+) for allogeneic stem cell transplantation, mainly in patients who lack an human leukocyte antigen-matched marrow donor. Since 1998, about 2,500 patients have received UCB transplants for a variety of malignant and non-malignant diseases. The vast majority of recipients were children with an average weight of 20 kg, however more than 500 UCB transplantations have already been performed in adults. The "naive" nature of UCB lymphocytes may explain the lower incidence and severity of graft versus host disease encountered in UCBT compared to the allogeneic transplant setting. Furthermore, UCB is rich in primitive CD16-CD56++ natural killer cells, which possess significant proliferative and cytotoxic capacities and can be expanded using interleukin-12 or 15, so as to mount a substantial graft versus leukemia effect. The major disadvantage of UCB is the low yield of stem cells, resulting in higher graft failure rates and slower time to engraftment compared to bone marrow transplantation. A rational approach thus involves ex vivo expansion of UCB-derived hematopoietic precursors.
近年来，脐带血已成为异基因干细胞移植中造血祖细胞（CD34+）的替代来源，主要用于那些缺乏人类白细胞抗原匹配骨髓供体的患者。自1998年以来，约2500例患者因各种恶性和非恶性疾病接受了脐带血移植。绝大多数受者是平均体重为20千克的儿童，不过成人中也已经进行了500多例脐带血移植。脐带血淋巴细胞的“原始”特性可能解释了与异基因移植相比，脐带血移植中移植物抗宿主病的发生率和严重程度较低的原因。此外，脐带血富含原始的CD16-CD56++自然杀伤细胞，这些细胞具有显著的增殖和细胞毒性能力，并且可以使用白细胞介素-12或15进行扩增，从而产生显著的移植物抗白血病效应。脐带血的主要缺点是干细胞产量低，与骨髓移植相比，导致更高的移植失败率和更长的植入时间。因此，一种合理的方法是对脐带血来源的造血前体细胞进行体外扩增。
