188Re标记抗人前列腺癌单克隆抗体及其在荷瘤裸鼠体内的放射性分布

为探讨188Re标记抗前列腺癌单克隆抗体7E11C5.3的方法及其生物学分布,采用2-巯基乙醇直接还原法制备188Re-7E11C5.3标记物,常规测定标记率和免疫活性,在荷瘤裸鼠体内检测标记物的生物学分布.结果显示,188Re-7E11C5.3的标记率为(93.16±2.18)%,免疫活性分数为(74.86±1.86)%;经尾静脉注入裸鼠体内后,肿瘤组织摄取率在24h达高峰,非肿瘤组织在4h摄取率较高,以后均随时间延长逐步降低;血液放射性清除迅速;24h时T/NT值达最大,至72h仍可保持在较高水平.结果表明,188Re-7E11C5.3在裸鼠体内对前列腺癌移植瘤有良好的靶向定位作用,可用于前列腺癌放射免疫显像和治疗研究.     

188Re-BAC5对鼻咽癌细胞影响的实验研究

采用直接标记法制备188Re-BAC5,并测定标记物的免疫活性,应用噻唑蓝(MTT)法观察188Re-BAC5对体外单层培养的鼻咽癌细胞(CNE-2)的抑制作用.建立鼻咽癌(NPC)肿瘤多细胞微球模型,观察188Re-BAC5对微球生长的抑制和破坏作用.对照组为188Re-BSA、188ReO4-.结果显示188Re-BAC5的标记率在80%以上,标记后的免疫活性分数为61%±15%.MTT法结果表明,188Re-BAC5组的抑瘤率比对照组明显提高(P＜0.05);在肿瘤多细胞微球的抑制实验中,188Re-BAC5对微球生长有强烈的抑制和破坏作用,疗效明显优于对照组.本实验提示,188Re-BAC5有可能在对人鼻咽癌的放射免疫治疗中起到良好的作用.     

放射性药物~(188)Re标记DTPA的制备和在大鼠体内的分布

球囊导管内充盈β放射性核素防治经皮冠状动脉成形术(PTCA)后再狭窄是一种崭新的技术, 其中,188Re是一种常用的放射性核素。为了尽可能降低在万一球囊破裂的情况下高剂量放射性对人体的损害,利用二乙三胺五醋酸(DTPA)迅速从泌尿系统排出的特点,通过探索188Re标记DTPA的方法和条件,成功地制备了188Re-DTPA化合物,并研究出最佳的标记条件从而使标记产率达到90%以上。188Re-DTPA和188ReO4-在大鼠体内分布的研究结果显示,甲状腺和胃肠道的放射性水平188Re-DTPA组明显低于188ReO4-组,188Re-DTPA经肾脏排泄明显快于188ReO4-,用MIRDOSE 3.0软件估算体内重要脏器的吸收剂量同样也显示了这一结果。188Re-DTPA组和188ReO4-组甲状腺的吸收剂量分别为0.041 nGy/Bq和0.563 nGy/Bq,胃的吸收剂量分别为0.043 nGy/Bq和0.118 nGy/Bq。因此,实验结果认为在血管内照射治疗中188Re-DTPA明显优于188ReO4-。     

188Re标记锡硫混悬液对荷人结肠癌裸鼠模型的治疗研究

以荷人结肠癌裸鼠为动物模型,研究了188Re标记的锡硫混悬液对荷人结肠癌的治疗效果、在裸鼠体内的稳定性及经瘤内注射后的体内器官分布,并用电镜观察了治疗后肿瘤的组织学变化.结果表明,188Re标记的锡硫混悬液有较好的抑瘤率,且在瘤内能长时间稳定存在.经188Re标记的锡硫混悬液治疗后,肿瘤细胞多为变性坏死.     

188Re标记抗CEA单克隆抗体及荷瘤裸鼠治疗实验研究

为建立18 8Re标记抗癌胚抗原 (CEA)单克隆抗体 (McAb )C50 的直接标记方法 ,探讨其标记条件 ,用抗坏血酸还原McAb ,并以葡萄糖酸钠为中间螯合剂 ,以氯化亚锡作还原剂 ,用188Re标记C50 。观察188Re标记McAb的体外稳定性 ,探讨还原剂SnCl2 浓度、螯合剂葡萄糖酸钠浓度、抗体浓度、加入抗体间隔的时间对标记物放化纯度的影响。SPECT显像观察荷瘤裸鼠瘤内注射188Re-C50 后放射性分布 ,对治疗后的瘤体行病理观察。实验结果显示 ,188Re标记C50 的合适条件为 :2 .2— 4 .0g/LSnCl2 、0 .3mol/L葡萄糖酸钠溶液、2 .5× 10 5— 5 .0× 10 5mol/LMcAb ,反应 2h后放化纯度可达 90 %。荷瘤裸鼠瘤内注射188Re -C50 后 ,放射性集中在瘤内 ,2周后瘤体明显缩小 ,镜下观察到肿瘤细胞破裂 ,坏死。     

Ad-hING4联合~(125)I粒子对裸鼠胰腺癌移植瘤的抑癌增效作用

本工作探讨腺病毒介导的人ING4基因(Ad-hING4)联合~(125)I粒子对裸鼠胰腺癌移植瘤的抑癌增效作用及其可能的机制.将本室构建的Ad-hING4腺病毒感染QBI-293A细胞,扩增后获得高滴度的病毒.建立25只裸鼠胰腺癌PANC-1皮下移植瘤模型,分成PBS对照组、空病毒Ad组、~(125)I粒子近距离放疗组、Ad-hING4基因治疗组、~(125)I粒子和Ad-hING4联合治疗组,进行抑瘤治疗实验;此后每5天测量1次肿瘤体积,20天后处死,计算抑瘤率和金氏q值.常规病理切片观察细胞生长形态、组织损伤程度和范围,并进行凋亡细胞计数(AI);免疫组化SP法检测肿瘤标本中微血管密度(MVD)、生存素SurvⅣin和活化的Caspase-3凋亡相关蛋白的表达.结果发现, ~(125)I粒子组、Ad-hING4组、联合治疗组抑瘤率分别达到34.19%(P<0.01)、31.50%(P<0.01)、67.15%(P<0.01),联合治疗组抑瘤率明显高于~(125)I粒子和Ad-hING4治疗组(P<0.01);病理切片检查显示近粒子处肿瘤细胞变性坏死,远离粒子处可见存活肿瘤细胞;三个治疗组凋亡指数(AI)、Caspase-3阳性细胞数明显高于PBS组(P<0.05),且联合治疗组明显高于~(125)I粒子和Ad-hING4治疗组(P<0.01);三个治疗组MVD值、SurvⅣin阳性细胞明显低于PBS组(P<0.05),且联合治疗组明显低于~(125)I粒子和Ad-hING4治疗组(P<0.01);Ad组与PBS组的各指标无显著性差异(P>0.05).可见~(125)I粒子、Ad-hING4可显著抑制裸鼠PANC-1胰腺癌移植瘤的生长,两者联用具有抑癌增效的协同作用,Ad-hING4有望作为一种新的放疗增敏剂;其抑瘤机制可能是通过下调SurvⅣin和上调Caspase3的表达,以诱导肿瘤细胞凋亡、抑制肿瘤血管形成.     

^188Re—labeled McAb 3H11 used as preventive for the peritoneal micrometasis of gastric cancer

In advancing gastric cancer, especially when the serous is invaded, the plantation of cancer cells in peritoneal is common and it affects patients' survival time severely. Based on successfully labeled McAb (monoclonal antibody) 3H11 with ~(188)Re, we investigated the effect of RIT (Radioimmuno-Therapy) with ~(188)Re-3H11 on preventing the peritoneal micrometastasis of gastric cancer cells in nude micc to increase the survival time. After 1×10~6 BGC-823 gastric cancer cells were injected into the peritoneal cavity of each mouse, 45BABL/C nude mice were divided into 9 groups. Each group received different doses of ~(188)Re-3H11 or ~(188)Re-IgG, or saline I.P.16 hours postoperation. The injected volume of each mouse was 1.0mL. The results showed that the survival time depended on the injected doses during 0 to 37 MBq. The survival time was 170±25.3d after 37MBq ~(188)Re-3H11 were treated. It was over 5 times more than that for the saline group and about 3 times more than that for 37 MBq ~(188)-Re IgG gro     

~(18)F-FHBG PET裸鼠移植瘤的HSV1-tk基因显像

制备了18F-FHBG基因探针,构建表达HSV1-tk报告基因的逆转录病毒表达载体pLXSN-tk,并建立人肝癌BEL-7402裸鼠双侧腋窝稍靠背侧皮下移植瘤模型.右侧移植瘤为实验组,左侧移植瘤为对照组,将逆转录病毒转染实验组移植瘤细胞.经裸鼠尾静脉注射18F-FHBG后,于10、30、50、70、90、110、130、150、170、190、210 min进行PET显像.结果显示:18F-FHBG未校正放化产率为4%-10%,经放射性HPLC分析测定放化纯度>95%.对照组移植瘤放射性分布未见明显增高;实验组移植瘤于注射18F-FHBG后50-210 min,PET显像见到灰阶可分辨放射性浓聚,150 min前摄取值逐渐升高,150 min达到高峰(摄取值为19.772kBq·mL-1),150 min后摄取值快速降低.实验组移植瘤的摄取值明显高于对照组移植瘤,两组移植瘤摄取值比值达4.99.表明18F-FHBG PET报告基因显像系统可用于监测HSV1-tk基因活体内靶细胞内的表达.     

18F-FDG对小鼠Lewis肺癌移植瘤抑制作用的实验研究

建立Lewis肺癌C57BL/6小鼠皮下移植瘤模型18只,按随机数字法分为高剂量18F-FDG治疗组、低剂量18F-FDG治疗组和对照组,每组6只,分别给予18F-FDG 18.5×107Bq、9.25×107Bq和0.2 mL等体积的生理盐水,于接种后第7天腹腔内一次给药,观察18F-FDG对Lewis肺癌移植瘤体积变化和瘤重的影响。22天后用流式细胞仪检测细胞凋亡,以免疫组化法检测bcl-2及Survivin基因的蛋白表达。发现18F-FDG高、低剂量组肿瘤抑瘤率及凋亡率明显高于对照组,Bcl-2及Survivin蛋白的表达明显低于对照组(P<0.05),与低剂量组相比,高剂量组与对照间差异更为显著(P<0.01)。这表明18F-FDG可明显抑制小鼠Lewis肺癌移植瘤生长,其机制可能与下调Bcl-2及Survivin蛋白的表达促进细胞凋亡有关。     

自噬活性调节胶质瘤起始细胞辐射敏感性的体内实验研究

为探讨自噬调节对胶质瘤起始细胞移植瘤辐射敏感性的影响,建立裸小鼠皮下移植瘤模型,测量肿瘤体积大小,比较抑瘤率检测雷帕霉素对移植瘤的辐射增敏作用;建立裸小鼠颅内移植瘤模型,观察裸小鼠生存期,HE染色观察移植瘤的生长。取两种模型中各组肿瘤组织做Western blot,分析自噬相关蛋白LC3表达。结果显示,裸小鼠皮下移植瘤模型中,联合治疗组的肿瘤体积明显小于阴性对照组和单纯辐照组(P>0.05),抑瘤率明显增加(P>0.05);在裸小鼠颅内原位移植瘤模型中,联合治疗组的裸小鼠生存期较阴性对照组和单纯辐照组明显延长,HE染色中可见联合治疗组肿瘤生长局限,与周围正常脑组织界限清楚。Western blot结果显示,两种模型中,联合治疗组中的比值LC3II/LC3I显著增加。研究表明,自噬激动剂雷帕霉素通过激活胶质瘤起始细胞的自噬活性,增加胶质瘤的辐射敏感性。     

Peptides radiolabelled with Re-186/188 and Tc-99m as potential diagnostic and therapeutic agents

Small peptide-based compounds have attracted an enormous interest as carrier molecules to selectively deliver radionuclides to target tissues, sparing critical normal organs. When looking for "matched pairs" of radionuclides,suitable for radiolabeling of peptides for diagnosis and therapy, technetium and rhenium represent an almost ideal constellation. The important role of technetium-99m and Re-186/188 is based on the decay characteristics, suitable for tumor diagnosis and therapy. Tc-99m and Re-188 are readily available by either a 99Mo/99mTc or the 188W/188Re radionuclide generator system. Furthermore, technetium and rhenium are chemically related and share structural as well as reactive similarities, which prompt an attractive "matched-pair" situation. This article shows an overview of 99mTc-and 186/188Re-radiolabeled peptides that have been tested for their potential use as imaging and therapeutic agents in oncological diseases.     

Peptides radiolabeled with Re-186/188 and Tc-99m as potential diagnostic and therapeutic agents

Small peptide-based compounds have attracted an enormous interest as carrier molecules to selectively deliver radionuclides to target tissues, sparing critical normal organs. When looking for ＂matched pairs＂ of radionuclides, suitable for radiolabeling of peptides for diagnosis and therapy, technetium and rhenium represent an almost ideal constellation. The important role of technetium-99m and Re-186/188 is based on the decay characteristics, suitable for tumor diagnosis and therapy. Tc-99m and Re-188 are readily available by either a ^99Mo/^99mTc or the ^188w/^188Re radionuclide generator system Furthermore, technetium and rhenium are chemically related and share structural as well as reactive similarities, which prompt an attractive ＂matched-pair＂ situation. This article shows an overview of ^99mTc- and ^186/188Re-radiolabeled peptides that have been tested for their potential use as imaging and therapeutic agents in oncological diseases.     

188Re-labeled McAb 3H11 used as preventive for the peritoneal micrometasis of gastric cancer

In advancing gastric cancer,especial1y when the serous is invaded,the p1antation of cancer cells in peritoneal is common and it affectspatients' survival time severe1y. Based on successfully labeledMcAb (monoclonal antibody) 3H11 with ¹⁸⁸Re,we investigated the effect of RIT (Radioimmuno-Therapy) with¹⁸⁸Re-3Hll on preventing the peritoneal micrometastasis ofgastric cancer cells in nude mice to     

~(188)Re—AEDP在小鼠中的生物分布及其与载体的依赖关系

用１８８Ｗ／１８８Ｒｅ发生器淋洗得到的１８８Ｒｅ示踪剂分别制备了无载体和有载体的１８８Ｒｅ－ＡＥＤＰ（１－氨基－亚乙基－１,１－二膦酸）,研究了这两种标记化合物在小鼠体内的分布,并讨论了载体对１８８Ｒｅ－ＡＥＤＰ生物分布的可能影响。实验结果指出：有载体的１８８Ｒｅ－ＡＥＤＰ有更高的骨摄取率和Ｔ／ＮＴ比,并且血液清除快,因而是一个有潜在价值的骨疼痛治疗剂。     

Biodistribution characteristics of ^188Re-TSC after TAE in rabbits bearing VX2 liver tumor

188Re-tin sulfur colloid (TSC) was prepared to compare its biodistribution characteristics with 188Re-macroaggregates album (MAA) after transhepatic arterial embolization (TAE) in rabbits bearing VX2 liver tumor. Labeling efficiencies of the 188Re-TSC and 188Re-MAA were 99.94%±0.04% and 99.95%±0.03%, respectively,and they were stable for 72 h in human serum. Sintigraphy and biodistribution in 31 rabbits bearing VX2 liver tumor after transcatherter hepatic arterial injection of the radiopharmaceuticals were performed, and relevant activity accumulated mostly in the tumor. The percentage of the injected dose per gram of wet tissue (%ID/g) of 188Re-TSC and 188Re-MAA were calculated. Tumor uptake of 188Re-TSC at 1 h and 24 h were 24.32%±11.93% and 21.88%±18.29%, and the radioactive ratios of tumor/liver were 70.89±19.58 and 17.42±13.96, respectively. Tumor uptake of 188Re-MAA at 1 h and 24 h were 38.78%±30.23% and 15.98%±96.64%, and the radioactive ratio of tumor/liver of 188Re-MAA were 39.71±95.06 and 8.13±4.61, respectively. 188Re-TSC is a potential radiopharmaceutical for the therapy of tumors.     

Preparation and primary biological evaluation of novel nitrido-188Re complexes/lipiodol

Two new nitrido-188Re complexes were prepared by a modified method in high yield.These complexes were stable in vitro.The biodistribution in normal mice showed that these nitrido-188Re complexes could accumulate in liver and dissipate quickly from almost all organs.TAE was performed with the use of lipiodol solutions of two complexes to rabbit VX2 liver tumor models.SPECT images showed that the two lipiodol solutions could remain in tumor for about 9 h (188ReN-NEPTDD/lipiodol) and 12 h (188ReN-NEMMPTDD/Iipiodol),respectively.     

188Re-HEDTMP 的合成及生物分布研究

在合成HEDTMP（羟乙基乙二胺三甲撑膦酸）的基础上，采用SnCl2作还原剂制备了其^188Re标记物。研究了标记物的兔SPECT骨扫描及在小鼠体内分布。结果表明，标记物骨显像良好，兔四肢、脊柱和颅骨图像清晰；小鼠体内分布表明，药物主要由小鼠骨骼摄取，其它组织的摄取率低，血清除快；通过与常用的骨肿瘤治疗剂比较，发现合成的标记物是非常有希望的治疗药物。     

含RGD序列多肽的~(188)Re标记及其生物分布

以fac-[188Re(CO)3(H2O)3]+为前体标记了含RGD的环状多肽H-c(RGDyK)(Pc1):75℃下反应30 min即可得到标记率和放化产率大于90%的目标产物188Re(CO)3-Pc1。此标记物在小牛血清及磷酸缓冲液(pH=7.4)中稳定性良好,Pc1对U87 MG细胞有良好的亲和力,半抑制常数(IC50)为84.9 nmol/L。生物分布数据显示,188Re-Pc1在血液内清除较快,且通过肝胆和肾代谢排出体外;在肿瘤内有一定的摄取。     

188Re直接标记单克隆抗体TGLA及其生物学评价

单克隆抗体TGLA是一种特异性靶向CD20的嵌合抗体,能有效杀伤肿瘤细胞和抑制肿瘤细胞增长,已用于B细胞淋巴瘤的临床治疗。本研究采用直接标记法,制备188Re-TGLA,并优化了标记条件。在最佳标记条件下,标记率可达93%,体外放置24 h后,放化纯度≥85%,体外稳定性良好。荷淋巴瘤裸鼠体内分布结果表明,188Re-TGLA在肿瘤的摄取较高,在24 h时为（6.46±2.01）ID%/g,提示188Re-TGLA可以作为一种有效的显像剂,但是为了更好的显像效果,可使用抗体片段进行标记,以缩短抗体的体内半衰期,更好地与188Re匹配。