混合脐血移植中HLA差异对植入的影响

Effects of HLA disparity of two umbilical cord blood units on human engraftment in SCID mice

目的 探讨HLA不同差异混合脐血移植的可行性和植入特性。方法 分别将 2份人HLA半相合或不相合混合脐血输入经亚致死量照射后的严重联合免疫缺陷 (SCID)小鼠 ,观察两组脐血在SCID小鼠体内的植入状况及造血和免疫功能重建特性。结果 两组混合脐血均可在受鼠体内植入 ,形成供 受混合嵌合体 ,并能重建多系造血 ,植入率差异无显著性 (P >0 .0 5 ) ,且未见明显不良反应。用多聚酶链反应 序列特异性寡核苷酸 (PCR SSO)探针检测人HLA DQB1基因发现 ,在多数受鼠体内只有 1份脐血植入 ,该份脐血为体外集落形成能力较高者 ,HLA半相合组有 3例出现来自供 受三者的多嵌合体。结论 HLA半相合及不合混合脐血移植可重建SCID小鼠造血和免疫功能 ,HLA相合程度不同的混合脐血移植与植入率无明显相关性 ,但相合程度较高者 ,似易于 2份脐血同时植入。

Objective To evaluate the feasibility and characteristics of human engraftment in HLA dispa rate cord blood transplantation. Methods Two human HLA haploidentical or HLA mismatched cord blood units were transplanted into sublethally irradiated severe combined immunodeficiency (SCID) mice. The characteristics of engraftment, hematopoietic and immunological reconstitution between the two groups were compared. Results Two mixed cord blood units can engraft in SCID mice with donor recipient chimerism and reconstitute hematopoiesis and immunological functions. No unfavorable factors had been observed. Only one of the two cord blood units which had higher colony forming ability in vitro could engraft in most SCID mice as shown by HLA DQB 1 gene detection. Two HLA haploidentical cord blood units were simultaneously engrafted in 3 SCID mice. Conclusion Double HLA haploidentical or HLA mismatched cord blood can engraft in SCID mice and reconstitute hematopoietic and immunological functions. HLA disparity has no significant effect on survival and engrafting rate. However, in less HLA disparity group, two cord blood units were prone to engraft simultaneously.