ALL病儿T淋巴细胞CD28表达及意义

目的探讨儿童B细胞型急性淋巴细胞白血病（ALL）治疗前后外周血T淋巴细胞表面CD28的表达及临床意义。方法采用流式细胞术，检测27例初发的B细胞型AI。L病儿化疗前后外周血T淋巴细胞表面CD28的表达，其中经化疗后达到完全缓解（cR）21例，未缓解（NR）6例。以同期23例健康体检儿童作为正常对照组。结果与正常对照组比较，治疗前初发ALL病儿外周血CD4^＋T淋巴细胞表面、CD8^＋T淋巴细胞表面CD28的表达均显著降低（t=21．56、44．02，P〈0．05）。化疗后CR组病）LPb周血CD4^＋T淋巴细胞表面、CD8^＋T淋巴细胞表面CD28较治疗前均显著升高（t=10．84、25．30，P〈0．05），而NR组病儿CD4^＋T淋巴细胞表面、CD8^＋T淋巴细胞表面CD28与治疗前比较差异无显著性（P〉0．05）。结论CD28是参与AI。L发病的重要共刺激分子，其表达异常可能是ALL的发病因素之一；其表达水平可能是判断ALI。预后及化疗敏感性的因素之一。

THE EXPRESSION OF CD28 IN T LYMPHOCYTES IN CHILDREN WITH ACUTE LYMPHOBLASTIC LEUKEMIA

Objective To investigate the expression of CD28 in peripheral blood T lymphocytes and its clinical signiti canoe in Children with B-call type acute lymphobiastic leukemia （ALL）, before and after chemotherapy. Methods By using FACS, the expression of CD28 was detected in 27 children with incipient B-cell type ALL. Of whom, complete remission after chemotherapy was noted in 21 patients, and no responce to the therapy was seen in six. Twenty-three healthy children of corresponding time period were served as controls. Results Compared with the control, the expression level of CD28 on CD4^＋ T and CD8^＋ T cell surface of ALL before chemotherapy was lower （t=21. 56,44.02;P〈0.05）, after the therapy, the expression of CD28 was elevated significantly （t=10.84,25.30 ;P〈0.05） ; in non-response ALl. children, the difference of CD28 expression was not significant versus before the therapy. Conclusion CD28 is an important costimulatory molecule involved in the pathogenesis of ALL, the abnormal expression of CD28 is probably one of the factors contributing to the occurrence of the disease. This is likely to become a parameter in the judgement of the therapeutic prognosis and sensitive to chemotherapy of ALL.