PD-1 在急性T淋巴细胞白血病细胞中的表达及其临床意义

[摘要] 目的：探讨PD-1 分子在急性T淋巴细胞白血病（T-ALL）患者来源的肿瘤细胞（T-ALL细胞）中的表达及其临床意义。方法：选用2015 年12 月江苏省中医院血液科提供的1 例T-ALL细胞、4 例健康志愿者提供的PBMC和博生吉医药科技（苏州）有限公司提供的人293T/PD-1 细胞，将T-ALL细胞经尾静脉注射到B-NDG小鼠构建T-ALL细胞异种移植瘤模型，用流式细胞术检测移植瘤小鼠脾中获得的细胞是否主要是由T-ALL细胞组成。用流式细胞术检测T-ALL细胞中PD-1 蛋白的表达，用RT-PCR进一步验证T-ALL细胞中PD-1 mRNA表达水平。对T-ALL细胞中PD-1 基因进行SNP测序，以检测PD-1 基因DNA序列是否发生改变。在体外使用PD-1 抑制剂研究其对T-ALL细胞增殖、凋亡以及相关因子mRNA表达水平的影响。结果：成功构建小鼠TALL细胞异种移植瘤模型，用流式细胞术确认了该例疾病是T-ALL。T-ALL 细胞中PD-1 mRNA和蛋白均高表达（均P<0.01）。PD-1 基因的第5 个外显子的一个碱基由胞嘧啶突变成胸腺嘧啶。在体外PD-1 抑制剂对T-ALL细胞的增殖和凋亡均无明显影响；PD-1 抑制剂上调抑癌蛋白IGFBP3 mRNA表达，降低促癌蛋白SULT1A3 mRNA表达（均P<0.01）。结论：PD-1 在T-ALL细胞中高表达，PD-1可作为临床上T-ALL诊断及治疗的靶点。

Expression of PD-1 in T-cell acute lymphoblastic leukemia cells and its clinical significance

[Abstract] Objective: To investigate the expression and clinical significance of PD-1 molecule in tumor cells (T-ALL cells) derived from the patient with T-cell acute lymphoblastic leukemia (T-ALL). Methods: T-ALL cells from one patient and PBMCs from four healthy volunteers provided by the Department of Hematology in Jiangsu Provincial Hospital of Traditional Chinese Medicine in December 2015, and human 293T/PD-1 cells provided by Persongen Bio Therapeutics (Suzhou) Co., Ltd. were used for this study. The mouse T-ALL xenograft model was constructed by injecting T-ALL cells into tail vein of B-NDG mice, and flow cytometry was used to verify whether the cells obtained from the spleen of transplanted mice were mainly consisted of T-ALL cells. Flow cytometry was used to study the protein expression of PD-1 in T-ALL cells, and RT-PCR was applied to further verify the mRNA expression of PD-1 in T-ALL cells. The PD-1 gene in T-ALL cells was sequenced by SNP genotyping to detect whether the DNA sequence of PD-1 gene changed. PD-1 inhibitor was used in vitro to study their effects on proliferation, apoptosis, and the mRNA expression levels of related factors in T-ALL cells. Results: The mouse T-ALL xenograft model was successfully constructed and verified by flow cytometry as T-ALL. PD-1 was highly expressed at both mRNA and protein levels in T-ALL cells (all P<0.01). A C-to-T mutation was detected in the fifth exon of the PD-1 gene. PD-1 inhibitor had no significant effect on proliferation and apoptosis of T-ALL cells in vitro; PD-1 inhibitor up-regulated the mRNA expression of tumor-suppressor protein IGFBP3 and decreased the mRNA expression of oncoprotein SULT1A3 (all P<0.01). Conclusion: PD-1 is highly expressed in T-ALL cells, and PD-1 could be used as a target for clinical diagnosis and treatment for T-ALL.