Harris D T
Department of Microbiology and Immunology, University of Arizona, Tucson 85721, USA.
Blood Cells. 1994;20(2-3):560-4; discussion 564-5.
Cord blood (CB) was analyzed for its alloreactive immune potential to evaluate its capacity to mediate graft vs. host disease (GVHD) and graft vs. leukemia (GVL) effects. Cord blood was observed to display minimal innate cytotoxic capacity but was capable of rapidly developing significant nonspecific natural killer cell-like effector mechanisms. Cord blood was unable to generate effective alloantigen-specific cytotoxic T lymphocytes (CTL), which was at least partially due to an altered lymphokine profile. The frequency of alloreactive T cells present in CB (whether assessed as total responding T-cell or CTL precursors) was greatly reduced as compared to adult peripheral blood lymphocytes (PBLs). However, the frequency of nonspecific effector cells was equivalent to PBLs. Significantly, CB T cells seemed to have undergone some type of developmental tolerance to maternal HLA antigens in utero, which could greatly increase the utility of CB in familial transplants. That is, CB T cells were unresponsive to noninherited maternal HLA antigens. Finally, CB demonstrated significant GVL capacity whether measured in vitro or in an animal model in vivo. Thus, the use of CB in most transplant settings should be free of the immunological problems associated with GVHD yet still be an effective mediator of GVL.
对脐血（CB）的同种异体反应性免疫潜能进行了分析，以评估其介导移植物抗宿主病（GVHD）和移植物抗白血病（GVL）效应的能力。观察到脐血显示出最小的固有细胞毒性能力，但能够迅速发展出显著的非特异性自然杀伤细胞样效应机制。脐血无法产生有效的同种异体抗原特异性细胞毒性T淋巴细胞（CTL），这至少部分归因于细胞因子谱的改变。与成人外周血淋巴细胞（PBL）相比，脐血中存在的同种异体反应性T细胞频率（无论评估为总反应性T细胞还是CTL前体）大大降低。然而，非特异性效应细胞的频率与PBL相当。重要的是，脐血T细胞似乎在子宫内对母体HLA抗原经历了某种类型的发育耐受性，这可以大大提高脐血在家族性移植中的效用。也就是说，脐血T细胞对非遗传的母体HLA抗原无反应。最后，无论在体外还是在体内动物模型中测量，脐血都显示出显著的GVL能力。因此，在大多数移植环境中使用脐血应该没有与GVHD相关的免疫问题，但仍然是GVL的有效介质。
