急性放射病异基因外周血造血干细胞移植后的免疫重建

Immune-reconstruction in acute radiation sickness after allogenic peripheral blood stem cell transplantation

目的观察急性放射病患者异基因造血干细胞移植前后免疫功能的变化规律。方法动态观察山东“10·21”辐射事故2例患者(分别为诊断极重度骨髓型和肠型急性放射病,于受照后7天分别进行了单倍体及HLA相合异基因外周血造血干细胞移植)移植前后淋巴细胞数、T细胞亚群、免疫球蛋白、NK细胞、中性粒细胞数等的变化情况。结果大剂量照射后免疫球蛋白呈下降趋势,移植后早期未观察到恢复趋势;照射后淋巴细胞数快速下降,移植后虽然有部分恢复,但仍然保持在较低水平(<0.5×109/L);照射后中性粒细胞有一过性升高,后迅速下降,移植后快速恢复;照射后NK细胞明显下降,移植后快速恢复,并基本保持在明显高于正常的水平。照射后早期CD4/CD8比值有一过性升高,后迅速下降,移植后有逐渐升高趋势,但未恢复正常。结论大剂量照射后免疫球蛋白、淋巴细胞数、NK细胞数、CD4/CD8比值等总体呈下降趋势提示,照射后细胞及体液免疫功能均快速受损。异基因造血干细胞移植后中性粒细胞数、NK细胞数等快速恢复,淋巴细胞数、CD4/CD8比值等有恢复趋势但恢复缓慢,免疫球蛋白未观察到恢复趋势,提示非特异性细胞免疫功能恢复快,但体液免疫功能及特异性细胞免疫功能恢复缓慢。

Objective To report immune-reconstruction in two patients with acute radiation sickness due to ^60Co radiation accident after stem cell transplantation. Methods Patient ＂A＂ and ＂B＂ were diagnosed as intestinal form of acute radiation sickness （ARS） and extremely severe degree bone marrow form of ARS, respectively. Peripheral blood stern cell transplantation was successfully performed/n these two patients. During their whole disease course, absolute lymphcyte count, neutrophil leukocyte count, T-lymphocyte subsets, natural killer （NK）, and immunoglobulin were sequentially determined. Results Immunoglobulin was decreased after irradiation without any recovery tendency after the transplantation. After irradiation, absolute lymphcyte count decreased rapidly, but recovered partially after the transplantation （maintained at 0. 5 × 10^9/L）. Neutrophilic leukocyte count rose rapidly to normal after the transplantation. NK was lowered obviously after irradiat/on, and it rapidly recovered to normal level after the transplantation, and maintained at a level higher than normal. After irradiation, the proportion of CD4/CD8 showed a transient rise, followed by an abrupt lowering. After the transplantation, it showed a tendency of elevation, but it did not recover to normal. Conclusions The tendency of lowering of immunoglobulin, lymphocyte count, NK cell count, and CD4/CD8 ratio indicate that there is a rapid deterioration of both cellular and humoral immunity after irradiation. Following the homogeneic peripheral blood transplantation, neutrophil count and NK cell count showed a rapid recovery, lymphocyte count and CD4/CD8 ratio also showed a tendency of slow elevation, but there is no sign of recovery of immunoglobulin. The results indicate that there is a faster recovery of cellular immunity.