单克隆抗体的放射性标记

单克隆抗体的放射性标记刘元方（北京大学技术物理系，１００８７１）１．引言在当代，放射化学的发展具有新时期的特色。除了传统的研究内容外，它与生命科学和环境科学有着紧密的联系。我们研究的重点是单克隆抗体（ＭｏＡｂ）的放射性标记化学￣［１］。近年来还用加速...     

用于放射性卤代药物合成的高速无载体固相标记法

本文研究了一种适合于卤素标记化合物的高分子氧化剂的合成及其性能, 研究了适合于某些卤代放射性药物合成的高速、无载体产物的固相标记法和固相反应。 用于肿瘤探针的药物带电诺丹明和肾功能显像剂胆固醇在固定化后, 将这两种药物进行固相法碘标记并对产物进行了鉴定, 得到了放射化学纯度大于95%, 放射性回收率高于96%的标记化合物, 实现了5分钟内完成放射性标记药物无需分离就可得到极高放化纯产物的高速标记法。本文还对其它能生成有机汞化合物的固相标记法进行了讨论。     

浅析药物化学中含有标记氢的药物命名

正确地对药物分子进行化学命名是药物化学教学中非常重要的部分。对于含有标记氢的药物分子的命名一直是药物化学教学中的难点。将药物化学教材中含有标记氢的化合物进行了归类,并分别举例来分析它们的命名。     

~(99m)Tc标记的叶酸肿瘤显像剂

叶酸受体在许多源于上皮组织的恶性肿瘤中高度表达,是目前肿瘤放射性显像研究的一个新的靶点。由于叶酸对于叶酸受体具有很高的亲合性,作为重要的特异性靶向介导分子,99mTc标记叶酸肿瘤显像剂已成为当前放射性药物的研究热点之一。本文对不同类型的99mTc标记的叶酸类放射性肿瘤显像剂的研究进展、应用情况和存在的问题进行了评述,探讨了99mTc标记叶酸显像剂的一般设计方法,并对其未来发展方向进行了展望。     

64Cu放射性药物化学

64Cu半衰期为12.7 h,其衰变过程既发射β+粒子(β+,0.655 MeV,17.8%),又发射β-粒子(β-,0.573 MeV,38.4%)。近20年来,随着铜配位化学的发展,新型配体不断出现(如DOTA、TETA、NOTA、CB-TE2A、C3B-DO2A等)。Cu(Ⅱ)的络合物在生物体内/外的稳定性不断提高,64Cu已经成功标记在氨基酸、多肽、蛋白、核酸等分子以及纳米颗粒上。64Cu可制成正电子显像药物用作诊断,同时也有发展为放射性治疗药物的潜力。新型铜配体和标记方法以及新的药物靶标的研究已经成为64Cu放射性药物研究的热点,至今已研制出了多种64Cu标记的放射性药物,如64Cu-ATSM是有效的肿瘤乏氧显像剂,64Cu-PTSM是优良的血流示踪剂等。本文旨在介绍64Cu(Ⅱ)几种主要类型的含氮配体以及64Cu标记的放射性药物在显像和治疗方面的最新研究进展,并展望其发展趋势。     

放射金属组学：以α核素靶向治疗药物为例

金属组学是综合研究生命体内(特别是细胞内)自由或络合的全部金属和类金属的含量、分布、形态、结构及功能的一门学科。作为金属组学的一个分支,放射金属组学重点研究放射性核素的制备和应用,特别是其在环境和生物体内的含量、分布、化学种态及功能等。靶向α治疗(Targeted alpha therapy, TAT)是一种利用发射α粒子的放射性核素与肿瘤选择性载体分子结合实现靶向癌细胞,进而对肿瘤组织造成杀伤作用的一种医疗方法,是放射金属组学在癌症治疗领域的重要应用方向。α粒子凭借高线性能量传递、短组织射程和较强的相对生物学效应,在放射性免疫和肿瘤治疗方面有着广阔的应用前景。以TAT药物为例,就常用α核素、TAT药物螯合剂及其标记的靶向载体、几种重要α放射性核素靶向治疗进展予以综述,并分析TAT药物研发的挑战和发展前景,从而展示放射金属组学在核医学领域特别是癌症治疗领域的研究进展。随着更多α核素的制备和更多靶向标记方法的建立,TAT药物有望用于多种疾病,这也需要新的放射金属组学方法的建立和应用。因此,放射金属组学在核医学领域具有良好应用前景。     

不同类型探针对免疫层析方法的分析灵敏度影响研究

为研究不同类型探针对免疫层析方法的分析灵敏度影响,该研究以17β-雌二醇(17f3-E2)为检测对象,采用磁性纳米材料标记7 μg/mL的17β-E2单克隆抗体(检测抗体)制备了传统探针,采用磁性纳米材料分别标记5 μg/mL的17P-E2单克隆抗体和5 μg/mL的羊抗鼠IgG多克隆抗体(第二抗体)制备了配对探针,采...     

基于双光子诱导荧光的肿瘤标志物CA125的实时动态可视化活检

糖链抗原CA125(Ag)是肿瘤早期及癌变期最重要的标识物,该文利用抗CA125单克隆抗体Ab125(Ab)特异性亲合抗原的原理,用制备的双光子荧光标记探针LP标记抗体(LP-Ab)以特异性识别CA125,用近红外激光激发抗原-抗体复合物(LP-Ab·Ag),利用复合物荧光实现对肿瘤标志物CA125的量化检测和实时动态成像。该方法简单易行,克服了单光子荧光检测中的光致毒与光漂白,且能显著提高成像的分辨率、清晰度与灵敏度,对肿瘤及癌变的早期诊断与预防具有重要意义。     

Tc标记的叶酸肿瘤显像剂

叶酸受体在许多源于上皮组织的恶性肿瘤中高度表达,是目前肿瘤放射性显像研究的一个新的靶点。由于叶酸对于叶酸受体具有很高的亲和性,作为重要的特异性靶向介导分子,^99mTc标记叶酸肿瘤显像剂已成为当前放射性药物的研究热点之一。本文对不同类型的^99mTc标记的叶酸类放射性肿瘤显像剂的研究进展、应用情况和存在的问题进行了评述,探讨了^99mTc标记叶酸显像剂的一般设计方法,并对其未来发展方向进行了展望。     

99mTc放射性药物化学

^99mTc放射性药物在科学研究和临床上已经得到了广泛的应用,但如何发展药效更好的药物以适应临床诊断的需求,依然是亟待解决的问题。新药物配体和金属核的引入以及新的标记方法的发展是目前^99mTc的放射性药物的热点。本文介绍^99mTc放射性药物化学的几种新标记方法,包括羰基锝标记的新型配体和新方法、^99mTc高价配合物的制备和应用等,旨在对有关研究者提供参考。     

Antigenic specificity of Escherichia coli alkaline phosphatase studied with monoclonal antibodies: Immunological characterization of E. coli and Shigella strains

Monoclonal antibodies (MoAb) to the alkaline phosphatase of Escherichia coli were produced from spleen cells of BALB/c mice primed with purified alkaline phosphatase of E. coli and SP₂O/Ag-14 myeloma cells. Five stable clones were established. They all produced antibodies which reacted by enzyme-linked immunosorbent assay (ELISA) with alkaline phosphatase of all E. coli (25 strains) independently of their origin (drinking water, saline water, surface water, faecal or clinical origin), and with that of four Shigella species (7 strains) tested. Four of these MoAb gave a positive reaction with 52 % (MoAb 4G10), 73 % (MoAb 4F8, MoAb 4G6) and 89 % (MoAb 3C8) of 14 other bacterial species (30 strains) studied, while one (MoAb 2E5) did not react with alkaline phosphatase of these unrelated bacterial strains and thus appeared specific for E. coli and Shigella species. This MoAb was still detectable in ascitic fluids at 1/500,000 in ELISA, and detected all E. coli strains in an indirect immunofluorescence assay at 1/100. It could therefore be used as a reagent for routine detection of E. coli in drinking water, food or clinical specimens.     

High-Performance Nucleic Acid Sensors for Liquid Biopsy Applications

Circulating tumour nucleic acids (ctNAs) are released from tumours cells and can be detected in blood samples, providing a way to track tumors without requiring a tissue sample. This “liquid biopsy” approach has the potential to replace invasive, painful, and costly tissue biopsies in cancer diagnosis and management. However, a very sensitive and specific approach is required to detect relatively low amounts of mutant sequences linked to cancer because they are masked by the high levels of wild-type sequences. This review discusses high-performance nucleic acid biosensors for ctNA analysis in patient samples. We compare sequencing- and amplification-based methods to next-generation sensors for ctDNA and ctRNA (including microRNA) profiling, such as electrochemical methods, surface plasmon resonance, Raman spectroscopy, and microfluidics and dielectrophoresis-based assays. We present an overview of the analytical sensitivity and accuracy of these methods as well as the biological and technical challenges they present.     

High‐Performance Nucleic Acid Sensors for Liquid Biopsy Applications

Circulating tumour nucleic acids (ctNAs) are released from tumours cells and can be detected in blood samples, providing a way to track tumors without requiring a tissue sample. This “liquid biopsy” approach has the potential to replace invasive, painful, and costly tissue biopsies in cancer diagnosis and management. However, a very sensitive and specific approach is required to detect relatively low amounts of mutant sequences linked to cancer because they are masked by the high levels of wild‐type sequences. This review discusses high‐performance nucleic acid biosensors for ctNA analysis in patient samples. We compare sequencing‐ and amplification‐based methods to next‐generation sensors for ctDNA and ctRNA (including microRNA) profiling, such as electrochemical methods, surface plasmon resonance, Raman spectroscopy, and microfluidics and dielectrophoresis‐based assays. We present an overview of the analytical sensitivity and accuracy of these methods as well as the biological and technical challenges they present.     

Chemical transformations of bacteriochlorophyll a and its medical applications

The review is devoted to methods of targeted chemical modifications of bacteriochlorophyll a. These methods provide an approach to the synthesis of derivatives with improved photophysical properties and increased hydrophilicity and are suited to the design of conjugates with other biologically active molecules utilized for fluorescence diagnosis and binary cancer therapy.     

Development of diagnostic models for canine osteoarthritis based on serum and joint fluid mid‐infrared spectral data using five different discrimination and classification methods

Osteoarthritis (OA) is an insidious joint disease that gradually leads to cartilage loss and the morphological impairment of other joint tissues. Therefore, early diagnosis and timely therapeutic intervention are of importance. Although there are a few diagnostic techniques used in clinics, these methods have various drawbacks. Infrared spectroscopy has emerged as an important analytical technique with wide applications in a variety of areas including clinical diagnosis. Research has shown that the presence of OA is associated with biochemical changes that are presumed to be reflected in serum or joint fluid. Hence, OA may be detected provided that serum or joint fluid is measured by infrared spectroscopy and appropriate data analysis methods are used to extract the diagnostic information from the infrared spectra. In this work, 5 discrimination and classification methods ([1] principal component analysis coupled with linear discriminant analysis, [2] principal component analysis coupled with multiple logistic regression, [3] partial least squares discriminant analysis, [4] regularized linear discriminant analysis, and [5] support vector machine) were used to build OA diagnostic models based on mid‐infrared spectra of serum and joint fluid. Useful diagnostic models were developed, indicating that infrared spectroscopy coupled with multivariate data analysis methods is very promising as a simple and accurate approach for OA diagnosis. The results also showed that models built from the 5 methods were different, as were the models' predictive performances. Therefore, choice of appropriate data analysis methods in model development should be taken into account.     

Computer-aided fault diagnosis in technical systems: An expert system for fault identification in the vacuum system of a mass spectrometer

We took a critical look on currently common methods for constructing expert systems and examined closely their applicability for computer-aided fault diagnosis. We deemed these methods not appropriate for this domain and presented our Knowledge Processing Facility KNOPF as an alternative. By means of KNOPF/MS, an expert system for computer-aided fault diagnosis in the vacuum system of a mass spectrometer implemented by using KNOPF, we demonstrated the applicability of our approach.     

近红外光谱技术结合主成分分析法用于子宫内膜癌的诊断

应用近红外光谱技术结合化学计量学方法研究了子宫内膜癌组织近红外光谱特征提取和早期诊断的可行性. 测定了154 例子宫内膜组织切片的近红外光谱, 选取适宜的波段和光谱预处理方法进行主成分分析, 很好地区分了癌变、增生和正常子宫内膜组织切片, 并且分辨出处于不同分化期的组织切片, 为子宫内膜癌的早期诊断提供了可靠依据. 该法快速、简便, 有望发展成为一种新型的肿瘤无创诊断方法.     

Effects of monoclonal antibody anti-EGF receptor on human nasopharyngeal carcinoma cell and other tumor cells

Three anti-EGF receptor MoAbs were used in these studies. Administration of MoAbs 3 and 176 inhibited tumor formation in nude mice by CNE-2, a poorly differentiated nasopharyngeal carcinoma cell line and A431, an epidermoid carcinoma cell line. When the same MoAbs were used in treatment against HeLa, a cervical carcinoma, tumor growth was not affected. The number of EGF receptors and apparent dissociation constants for 125I-EGF on CNE-2 and A431 was 1.3 x 10(5)/cell (Kd 7.7 x 10(-8) mol/L) and 1.4 x 10(6)/cell (Kd 2.4 x 10(-9) mol/L), respectively. Both MoAbs 3 and 176, capable of competing with EGF for receptor binding, showed significant tumor growth inhibition. MoAb 101 was incapable of blocking the binding of EGF to its receptor, and not as effective as MoAbs 3 and 176 in tumor growth inhibition. Our observation is that the MoAb anti-EGF receptor is cytostatic rather than cytocidal, in vitro against CNE-2 and A431.     

Molecular characterization of selected dermatophytes and their identification by electrophoretic mutation scanning

Dermatophytes are fungi that can be contagious and cause infections in the keratinized skin of mammals, including humans. The etiological diagnosis of dermatophytosis relies on a combination of in vitro‐culture and microscopic methods. Effective molecular tools could overcome the limitations of conventional methods of identification. In the present study, following phenetic identification as M. canis, M. fulvum, M. gypseum, T. mentagrophytes and T. terrestre, we genetically characterized key dermatophytes, employing the sequences of the first and second internal transcribed spacers of nuclear ribosomal DNA as well as part of the chitin synthase‐1 gene, and assessed the utility of these DNA regions (based on levels of nucleotide variation within and among species/taxa) as markers for the classification of species and genotypes. Employing partial chitin synthase‐1 gene as the marker, we also established a PCR‐coupled SSCP approach as a diagnostic/analytical mutation‐scanning tool. This tool should facilitate fundamental investigations of the ecology, epidemiology and population genetics of dermatophytes and, importantly, should assist in allowing a more rapid diagnosis of dermatophytoses in humans and other animals, thus overcoming the significant delays in targeted chemotherapy following diagnosis using conventional methods. (Nucleotide sequence data reported in this paper are available in the EMBL, GenBank and DDJB datadases under accession numbers FJ897707–FJ897713 (ITS‐1), FJ897714–FJ897720 (ITS‐2) and FJ897700–FJ897706 (pchs‐1)).     

免疫分析与细胞检测新原理与新方法研究

将分析化学与临床诊断相结合,发展临床检测新原理、新方法已成为人类健康的前沿领域之一,其中免疫分析,特别是多标志物同时免疫检测新方法的发展,与细胞检测已成为人们关注的课题。本文综述了近3年来这方面的研究进展, 并简要介绍了免分离、准无试剂和全无试剂安培免疫分析,空间分辨多通道安培芯片,底物区带分辨、通道分辨和通道-底物区带二维分辨化学发光免疫分析等多种免疫分析新概念,细胞检测与表面增殖监测、细胞毒效应研究与药敏检测新方法,对其在肿瘤临床诊断中的应用也作了总结。