188Re

摘要： [目的]探讨放射性核素188Re间接法标记小分子肽cNGQGEQc的可行性,并观察188Re-cNGQGEQc对肺腺癌A549细胞的体外抑制作用.[方法]188Re-cNGQGEQc和188Re-cNAQAEQc(阴性多肽)的制备采用双半胱氨酸(EC)为双功能螯合剂的间接标记法,测定标记多肽的标记率、比活度、放化纯度、脂水分配系数,并观察在正常人血清中的稳定性.采用CCK-8法测定188Re-cNGQGEQc对体外培养的肺腺癌A549细胞株的抑制效应,观察不同放射性剂量的188Re-cNGQGEQc对肺腺癌A549细胞增殖的抑制作用,计算相对抑制率及半数有效抑制浓度(IC50),并与188Re标记的阴性多肽及188ReO4-进行比较.[结果]188Re-cNGQGEQc的标记率为(90.24±1.58)％,比活度为(4.07±0.14)TBq/(mmol/L),C18柱纯化后放化纯度为(98.42±0.32)％,188Re-cNGQGEQc的脂水分配系数lgP为(-2.90±0.03),在37°C正常人血清中放置24 h其放化纯度为(89.08±0.94)％.抑制性实验结果表明188Re-cNGQGEQc对肺腺癌A549细胞的增殖具有显著的抑制作用,且与放射剂量呈明显正相关;而且188Re-cNGQGEQc的IC50值为44.88×107 Bq/L,明显低于阴性多肽的93.45×107 Bq/L和188ReO4-的99.60×107 Bq/L(P<0.01).[结论]使用双功能螯合剂EC建立了标记率高、体外稳定的188Re标记小分子肽的方法,体外实验证实188Re-cNGQGEQc能有效地抑制肺腺癌A549细胞的增殖,研究结果为后续开展小分子多肽的放射靶向治疗肺癌的体内应用提供实验基础.

摘要： 目的 探讨CD45单抗及188Re-亲和素(Avidin)二步法预定位对人淋巴瘤Raji细胞的放射免疫效应.方法 188Re对CD45单抗及Avidin的标记采用直接标记法,采用纸层析法测定标记率及放化纯度.分析188Re-CD45单抗与Raji细胞的体外结合能力,并进行体外竞争结合实验,采用CCK-8法测定二步法预定位组、188Re-CD45单抗组、188Re-Avidin组和188ReO4-组对Raji细胞的增殖抑制效应,计算Raji细胞存活率和抑制率.结果 188Re-CD45单抗与Raji细胞的特异性结合率为(70.92±1.91)％,同时加入188Re-CD45单抗和过量的CD45单抗,则细胞结合率平均为(7.96±0.87)％.二步法预定位组、188 Re-CD45单抗组、1888Re-Avidin组和1888ReO4-组对Raji细胞的增殖均有抑制作用,抑制率与放射性活度呈正相关(r=0.907 ～0.992,P＜0.05);在相同放射性活度下,二步法预定位组在各时间点的抑制作用均高于188 Re-CD45单抗组、188Re-Avidin组和188 ReO4-组(t=124.76 ～ 607.98,P＜0.05).结论 188 Re-CD45单抗可特异性地与Raji细胞结合,CD45单抗及188 Re-Avidin二步法预定位对人淋巴瘤Raji细胞具有明显的抑制作用.%Objective To study the effect of two-step pretargeting radioimmunotherapy of CD45 McAb and 188Re-Avidin on lymphoma Raji cell line.Methods The CD45 McAb and Avidin were directly labeled with 188Re,and the labeling efficiency and radiochemical purity were measured by the paper chromatography.The specific binding test and competition binding test between 188 Re-CD45 McAb and Raji cells in vitro were also performed.CCK-8 assay was used to determine the inhibition effect on Raji cell proliferation in the pretargeted group,188Re-CD45 McAb,188Re-Avidin and 188ReO4 groups,then the cell survival and proliferation inhibition rate were calculated.Results The specific cell binding rate of 188Re-CD45 McAb with Raji cells was (70.92 ± 1.91) ％,in the competition group,the binging rate of 188Re-CD45 McAb with Raji cells was only (7.96 ± 0.87)％.The Raji cells proliferation was inhibited in all groups with 188Re radiolabel,and the inhibition rate was positively correlated with the radioactivity dose (r=0.907-0.992,P ＜0.05).However,at the same dose,the inhibition effect in the group of two-step pretargeting at each time point were all stronger than those of 188Re-CD45 McAb,188Re-Avidin and 188 ReO4-alone (t =124.76-607.98,P ＜ 0.05).But there was no significantly statistical difference in the inhibitory effect between the groups of 188Re-Avidin and 188ReO4-(P ＞ 0.05).Conclusions It is confirmed that 188Re-CD45 McAb could be specifically bound to Raji cells,and the two-step pretargeting of CD45 McAb and 188Re-Avidin has obvious inhibitory effect on the Raji cell proliferation.

摘要： Objective To establish a two-step pretargeting approach to lymphoma radioimmunoimaging in mice using biotinynaled CD45 monoclonal antibody (McAb) and 18 Re-avidin in a tumor-bearing mouse model. Methods Six Nod-Scid mice bearing lymphoma cell xenograft were randomized to receive either an intravenous injection of 50μg/200μL biotinyled CD45 McAb followed 24 h later by an intraperitoneal injection of 3.7 MBq (50μg/100μL) 18 Re-avidin (two-step pretargeting group), or a single intravenous injection of 3.7 MBq (100μg/100μL) 18 Re-CD45 McAb (control group). SPECT was performed at 0.5, 1, 6 and 23 h post-injection to characterize 18 Re isotope biodistribution. At 24 h pos-injection, the mice were sacrificed for measurement of radioactivity uptake in the tumor and normal tissues and calculation of the tumor-to-non-tumor (T/NT) ratios. Results SPECT showed that the two-step pretargeting method resulted in a low radioactivity in the blood pool during the imaging and a concentrated radioactivity in the liver and spleen. The transplanted tumor began to be displayed at 1 h post-injection and was clearly displayed at 1-6 h;the images were clear even at 23 h. With the two-step pretargeting method, the radioactive uptake at 24 h post-injection were (1.34±0.52)%, (6.77±2.32)%, and (2.81±1.25)%in the tumor, kidney and liver, respectively, with low radioactivity levels in other organs and high tumor/blood and tumor/muscle ratios (4.28±0.82 and 8.00± 0.88, respectively). In the control group, SPECT revealed intense radioactivity in the liver, spleen, and kidneys with obscure display of the tumor;at 20 h, the radioactivity in the blood pool remained high but that in the tumor was low, and the tumor/blood and tumor/muscle ratios at 24 h were only 0.58±0.06 and 3.21±0.24, respectively. Conclusion Compared with 18 Re-CD45 McAb, the two-step pretargeting approach exhibits a good specificity in targeting lymphoma with an increased T/NT ratio in mice and allows early tumor display at 1 h post-injection.%目的 建立CD45单抗介导的188Re-亲和素二步法预定位方法,观察其在荷瘤小鼠体内的生物学分布特点,评价其在淋巴瘤治疗应用中的可行性.方法 CD45单抗及亲和素的188Re标记采用直接标记法,纸层析法测定标记率及放化纯度.取人Raji细胞移植瘤Nod-Scid小鼠6只,随机分为2组,实验组为二步法预定位组,对照组为188Re-CD45单抗组.注药后0.5、1、6和23 h分别进行SPECT显像;同时于注药后24 h分别处死2组荷瘤小鼠,取脏器组织及肿瘤,称重,测量放射性计数,经放射性衰变校正后计算各脏器%ID/g和靶/非靶(T/NT)比值.结果 188Re-CD45单抗的标记率(82.52±2.92)%,放化纯度>90%;188Re-亲和素标记率平均为(80.83±3.48)%.荷瘤小鼠SPECT显像及体内生物分布结果示:在实验组整个显像期间血池内放射性均较低,肝脏和脾脏内见较多放射性浓聚,注射后1h移植肿瘤见显影,随着时间的延长瘤内放射性分布增多,1~6h肿瘤显影渐清晰,并持续到23 h;注射标记物后24 h,肿瘤摄取(%ID/g)为(1.34±0.52)%,肾脏和肝脏摄取(%ID/g)分别为(6.77±2.32)%和(2.81±1.25)%,其他脏器内的%ID/g保持在较低水平,24 h肿瘤/血液比值为(4.28±0.82),肿瘤/肌肉比值为(8.00±0.88).而对照组则可见肝脏、脾脏和肾脏内有明显放射性聚集,肿瘤部位显影模糊,20 h血池内仍见有较多放射性分布,肿瘤部位见少量放射性集聚;注射标记物后24 h,肿瘤/血液比值为(0.58±0.06),肿瘤/肌肉比值为(3.21±0.24).结论 与188Re-CD45单抗组相比较,CD45单抗介导的188Re-亲和素二步法预定位组在淋巴瘤荷瘤小鼠体内具有较好的特异性和靶向性,明显提高肿瘤的T/NT比值,标记物注射后1 h即可使肿瘤显影.

摘要： 研究放射性核素铼(188Re)标记脑胶质瘤U87-EGFRvⅢ(Epidermal Growth Factor Receptor Variant Ⅲ)细胞反义寡核苷酸序列的制备方法,探讨其作为脑胶质瘤反义显像剂的可能性.采用细胞指数富集的配基系统进化技术(Cell-based Systematic Evolution of Ligands by Exponential Enrichment,Cell-SELEX)筛选脑胶质瘤U87-EGFRvⅢ细胞,得到一段高亲和力的反义寡核苷酸序列U2,然后采用直接标记法进行188Re的放射性标记,按照正交实验设计进行188Re最佳标记条件的摸索,纸层析法测定标记率,通过体外稳定性实验评价188Re-U2的放化特性,测定标记物静脉注射后在大耳兔不同时相血液放射性清除曲线,应用SPECT显像观察标记物在兔体内的放射性动态分布变化.结果表明:在最佳标记条件下188Re-U2的标记率为70％±14％;经Sep-PaK C18反相柱分离纯化后,188Re-U2在生理盐水和血清中37°C下放置24h的放化纯度分别为70.6％和95.55％;188Re-U2在兔体内的血放射性清除迅速,主要通过肾脏排泄,其余脏器内放射性均较低.188Re直接法标记U87-EGFRvⅢ细胞反义寡核苷酸U2的方法简单,具有良好的标记率和体内外稳定性,并且体内分布动力学特性也比较理想.

摘要： 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188 Re-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,188 Re-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188 Re匹配.%Monoclonal antibody TGLA is a specific targeting CD20 chimeric antibody. It can kill tumor cells and inhibit tumor cells' growth effectively, which has been applied to clinical therapy of lymphoma cell B. Monoclonal antibody TGLA was labeled with 188Re, directly and got the target compound 188Re-TGLA. Moreover, this work improved the reduction conditions and labeling conditions of 188Re. The labeling yield reached as high as 93% at the optimum conditions. The vitro stability was good with the radiochemical purity of more than 85% after 24 hours in vitro. The biodistribution of the 188Re-TGLA in lymphoma bearing nude mice showed high uptake in tumor ((6. 46±2.01)ID%/g, 24 h) , implied that 188Re-TGLA can be used for imaging effectively. However, in order to get better imaging, antibody fragment with short half life in vivo should be used for labeling of 188Re.

摘要： Objective With direct-labeling method of CD45 McAb with 188Re, to investigate its bio-distribution character in normal mice. Methods The disulfide bond in the molecule of CD45 monoclonal antibody was reduced to form a mercapto group by the mercaptoethanol (2-ME). The labeling was conducted by stannous chloride used as reductant of 188Re, and sodium glucoheptonate as intermediate.weak ligands, then 188Re was directly labeled CD45 mAb alone; The reaction mixture was separated and purified throuth the PD-10 column;Labeling efficiency and radiochemical purity were measured by the paper chromatography. Then stability of 188Re labeled CD45 McAb was determined in vitro. The biodistribution in the healthy Kunming mice after intravenous injection of 188Re-CD45 McAb was determined. Results The labeling efficiency of 188Re-CD45 McAb was (85.25±2.63)%, and radiochemical purity was (92.54±3.56)%. The specific activity was (2.06±0.07) TBq/mmol;The radiochemical purity of 188Re-CD45 McAb was (64.33±1.53)% after incubating 24 h in room temperature. While mixed the saline and healthy rat serum at 37°Cfor 24 h, the radiochemical purity was (64. 2±3. 77)%and(56. 7±4. 16)%, respectively. The biodistribution result showed that the radioactivity in body was mainly distributed in kidney and liver, followed by lung, bone and blood. Conclusion The method of direct-labeling CD45 McAb with 188Re is not only simple, but also has high labeling efficiency. 188Re-CD45 McAb has good stability in vitro. After injected intravenously, radioactive label is mainly excreted through kidneys with a higher accumulation in liver, and it accords with the in vivo kinetics characteristic of labeled antibody.%目的：利用188Re直接法标记CD45单抗，探讨其在正常小鼠体内的生物学分布特性。方法应用2-巯基乙醇（2-ME）还原CD45单抗分子中的二硫键形成巯基；以氯化亚锡作为188Re的还原剂，葡庚糖酸钠为中间弱配体，188Re直接标记CD45单抗；PD-10层析柱分离纯化，纸层析法测定标记率与放化纯；鉴定188Re-CD45单抗的体外稳定性；研究188Re-CD45单抗在正常小鼠体内的生物分布特性。结果188Re-CD45单抗的标记率平均为（85.25±2.63）%，PD-10柱纯化后的放化纯为（92.54±3.56）%，比活度平均为（2.06±0.07）TBq/mmol；室温下放置24 h，188Re-CD45单抗放化纯为（64.33±1.53）%；在鼠血清和生理盐水中37°C下孵育24 h后，其放化纯仍有（64.2±3.77）%和（56.7±4.16）%。小鼠体内生物分布显示，188Re-CD45单抗主要分布于肾脏和肝脏，其次是肺脏、骨骼和血液。结论188Re直接法标记CD45单抗的方法简单易行，标记率较高，具有良好的体外稳定性；188Re-CD45单抗静脉注射后，体内放射性主要经肾脏排泄，并在肝脏有较高的浓聚，符合标记抗体的体内分布规律。

摘要： 叶酸受体在多种肿瘤细胞中过表达是癌症治疗中一种可能的靶向药物结合位点.我们将五代PAMAM 树状大分子用叶酸和 1B4M-DTPA修饰,然后用188Re进行放射性标记.化合物的标记产率为67.5%,分离后的放射化学纯度大于95%,并表现出良好的体外稳定性,为该化合物在叶酸受体靶向肿瘤治疗应用中奠定了基础.

摘要： 采用188Re标记含有天冬酰胺、甘氨酸、精氨酸(Asn-Gly-Arg,NGR)序列的肿瘤血管靶向性短肽,得到188Re-NGR,观察了188Re-NGR在荷HepG2肝癌细胞严重联合免疫缺陷(Severe Combined Immunodeficiency,SCID)裸鼠肿瘤模型中的生物分布,并对其进行了SPECT显像.结果显示,188Re-NGR的标记率＞85%,放化纯度＞90%.188Re-NGR在肿瘤模型鼠体内的生物分布显示,注射188Re-NGR后12 h,肿瘤放射性摄取达最高,为(4.62±0.71)%ID/g,24 h时仍有(2.01±0.38)%ID/g,说明标记物在肿瘤内停留时间较长;竞争性抑制组中,12 h肿瘤放射性摄取为(1.43±0.61)%ID/g,明显低于实验组.肿瘤与肌肉组织的放射性摄取比(T/NT)12 h为4.76.注射后1 h肿瘤可显像,4～8 h显像逐渐清晰,12 h时更为清晰.以上结果提示,188Re-NGR具有良好的肿瘤血管靶向性.%To evaluate its radiochemical characteristics, biodistribution and imaging for nude mice bearing HepG2, 188Re-NGR was prepared directly with 2-mercapto-ethanol as reductant and sodium gluconate as middle ligand. The labeling yield of 188 Re-NGR was more than 85％, and the radiochemical purity (RCP) was more than 90％. In vivo, 188Re-NGR can specifically bind with tumor. The tumor uptake was (2.84±0.51)％ID/g at 1 h after injection, the uptake was(4. 62±0. 71)％ID/g at 12 h and remains (2.01±0.38)％ID/g for 24 h, the contrl group was (1.43±0.61)％ID/g. The ratio of tumor to muscle was 4.76 at 12 h. The xenografted tumor became visible at 1 h and was the most clearly at 12 h. The results showed that NGR had the function of good targeting.

摘要： Objectives To study the inhibitory activity of internal irradiation of interventional radionuclide 188 Re in thermosensitive chitosan on mouse transplanted tumor H22 (liver cancer).Method The tumor-bearing mice were divided into 7 groups randomly, including model control, 188Re(0.1mCi) group, 188Re-S(0.1mCi) group, 188Re + CS(0.1mCi)group, 188Re + CS (0.2mCi)group, 188Re-S + CS 0.1mCi)and188Re-S + CS(0.2mCi)group.The mice tumor was injected with corresponding reagent respectively, and the inhibitoy rate of tumor was observed after administrated.Results The growth of tumors in 188Re + CS group and 188Re-S + CS group was slowed.the tumor inhibitory rate reached the highest level after 6 days therapy, which respectively was 67.35％ and 67.81％.Conclusions Internal irradiation of interventional radionuclide 188 Re in thermosensitive ehitosan had the effect of inhibitory mice liver cancer.%目的 研究温敏型壳聚糖(chitonsan CS)介入核素188Re内照射对小鼠移植性肝RW(H22)的抑制作用.方法 建立小鼠肝癌(H22)模型后随机分成7组,即模型对照组、.88Re(0.1mCi)组、188Re-S (0.1mCi)组、188Re +CS (0.1 mci)组、188Re + CS (0.2mCi)组、188Re+硫胶体+壳聚糖(188Re-S + CS 0.1 mCi)组和188Re-S + CS (0.2mCi )组.各组动物瘤内分别注射相应试药,测定肿瘤抑制率.结果 188Re + CS组和188Re-S + CS组肿瘤生长速度减慢,肿瘤生长延迟,肿瘤抑制率在治疗后6d最高,抑制率分别为67.35%和67.81%.结论 温敏型壳聚糖介入核素188Re内照射对小鼠肝癌(H22)具有一定的抑制作用.

摘要： 本工作通过合成得到配体EDTMP,制备出标记率较高的117Snm (188Re、153Sm)配合物.对3种配合物的体外稳定性、亲脂性进行了考察;对其生物分布作了初步探索,评价了188Re-EDTMP、117Snm-EDTMP作为骨肿瘤治疗药物的可能性.结果表明,3种配合物都易于被骨摄取,但188Re-EDTMP的体内稳定性较差,容易被洗脱,需要进一步改善;与已用于临床应用的153Sm-EDTMP相比,117Snm-EDTMP的小鼠体内分布与其趋势比较一致,在靶组织(脑骨和四肢骨)上的浓集率较高,显示出可用于骨系统疾病治疗的可能性,有进一步研究的价值.