抑制T细胞CDK9对TLR5靶向监测同种异体移植排斥的影响  

Impact of CDK9 inhibition for T cells on TLR5-targeting monitoring during allorejection

作　　者：李晓梅 梁婷 张超 曹慧 侯桂华 LI Xiaomei;LIANG Ting;ZHANG Chao;CAO Hui;HOU Guihua(Biomedical Isotope Research Center,Basic Science of Medical School,Shandong University,Jinan 250012,Shandong,China)

机构地区：[1]山东大学基础医学院生物医学同位素研究中心,山东济南250012

出　　处：《山东大学学报（医学版）》2018年第7期1-6,共6页Journal of Shandong University:Health Sciences

基　　金：国家自然科学基金(81371601)

摘　　要：目的探讨抑制T细胞中的细胞周期蛋白依赖性激酶9(CDK9)对Toll样受体5(TLR5)靶向监测同种异体移植急性排斥的影响。方法 Iodogen法碘化标记抗TLR5抗体(^(125) I-anti-TLR5),体外实验分析特异性及稳定性,脾细胞与^(125) I-anti-TLR5结合及解离实验分析脾细胞与标记物的亲和力;构建C57BL/6-SCID小鼠T细胞介导同种异体移植急性排斥模型,LDC000067(CDK9抑制剂)(5μmol/L)或等量PBS处理BALB/c小鼠T细胞并过继转输至模型小鼠,分为对照组(n=14)、抑制组(n=16),另有抑制组小鼠在注射^(125) I-anti-TLR5之前注射未标记抗TLR5抗体(10 mg/kg)为阻断组。观察抑制T细胞CDK9对同种异体移植物生存期影响及局部病理学改变;于对照组排斥高峰期时,对照组和抑制组小鼠尾静脉注射^(125) I-anti-TLR5,分析生物学分布、动态全身磷屏自显影显像及标记物的TLR5靶向性。结果抑制组移植皮片生存期(28.20±2.77)d,而对照组为(20.00±1.58)d;炎性浸润明显减少,TLR5表达增加。制备的^(125) I-anti-TLR5标记率达96.2%,体外稳定性良好(72 h仍保持在90%以上)。CDK9抑制剂体外处理后,受体鼠脾细胞与标记物的结合率增加,解离率降低(P均<0.05)。体内生物学分布研究表明,标记物主要经肝肾代谢,移植皮片放射性浓聚明显,抑制组72 h靶/非靶比值(3.70±0.16)较对照组(2.02±0.06)增高(P<0.05)。全身磷屏放射自显影结果显示,注射后48 h移植皮片显影,抑制组较对照组显像明显,且放射性浓聚持续时间长,阻断组未见明显放射性浓聚。结论抑制T细胞CDK9可明显延长同种异体移植物生存期,促进^(125) I-anti-TLR5同种异体移植物局部浓聚,有利于体内TLR5靶向同种异体移植急性排斥监测。Objective To explore the impact of T cells Cyclin-dependent kinase 9（ CDK9） inhibition on Toll-like receptor5（ TLR5） targeting monitoring of acute allorejection. Methods 125 I-anti-TLR5 was prepared with Iodogen method. Label rate,stability and cell uptake and dissociation between spleen cells and 125 I-anti-TLR5 were analyzed. AllograftedSCID mouse models were established through T cells adoptive transferred and were divided into control group and CDK9 inhibition group. Another group of mice were injected with 125 I-anti-TLR5 before injection of unlabeled anti-TLR5 antibody（ 100 μL 10 mg/kg body weight） as a blocking group. Allograft survival and graft histopathology were observed. 125 I-anti-TLR5 was injected through tail vein at the peak of the control group rejection,and the biodistribution and whole-body phosphor-autoradiography were analyzed. Results T cells CDK9 inhibition apparently prolonged allograft survival from（ 20.00±1.58） d to（ 28.20±2.77） d,and weaken inflammation and increased expression of TLR5 on allografts. 125I-anti-TLR5 was prepared successfully with high label rate（ 96.2%） and stability（ 〉90% at 72 h）.Recipient spleen cells-pretreated with CDK9 inhibitor increased the uptake ratio of 125 I-anti-TLR5 and reduced the dissociating ratio（ P 〈0.05）. Ex vivo biodistribution studies revealed that 125 I-anti-TLR5 could be accumulated in skin allograft.T/NT ratio（ allograft/oposite skin） of CDK9 inhibition group was higher than that of control group（ 3.70±0.16 vs 2.02±0.06） at 72 h post injection. Whole-body phosphor-autoradiography imaging showed that clear graft localization was developed at 48 h,lasting longer in CDK9 inhibition group than control group,and no obvious accumulating imaging was noted in blocked group. Conclusion The inhibition of CDK9 on T cells can prolong allograft survival through reducing inflammation and promoting the expression of TLR5 of allograft,which may favor in vivo monitoring of TLR5 targeting acute allorejection.

关 键 词：放射性碘125 TOLL样受体5 细胞周期蛋白依赖性激酶9 磷屏自显影显像 同种异体移植 

分 类 号：R817.33[医药卫生—影像医学与核医学]