北京地区人群诺瓦克样病毒血清抗体水平调查

为了解诺瓦克样病毒在我国人群行情况。采用间接酶联免疫吸附法，分别以重组杆状病毒表达的Ｎｏｒｗａｌｋ（ｒＮＶ）和Ｍｅｉｘｃｏ（ｒＭＸ）病毒样颗粒为抗原，检测了北京地区１１０９份不同年龄人群血清标本中的特异性ＩｇＧ抗体。  

Expression of cholera toxin B subunit oligomers in transgenic potato plants

A gene encoding the cholera toxin B subunit protein (CTB), fused to an endoplasmic reticulum (ER) retention signal (SEKDEL) was inserted adjacent to the bi-directional mannopine synthase P2 promoter in a plant expression vector containing a bacterial luciferase AB fusion gene (luxF) linked to the P1 promoter. Potato leaf explants were transformed by Agrobacterium tumefaciens carrying the vector and kanamycin-resistant plants were regenerated. The CTB-SEKDEL fusion gene was identified in the genomic DNA of bioluminescent plants by polymerase chain reaction amplification. Immunoblot analysis indicated that plant-derived CTB protein was antigenically indistinguishable from bacterial CTB protein, and that oligomeric CTB molecules (Mr 50 kDa) were the dominant molecular species isolated from transgenic potato leaf and tuber tissues. Similar to bacterial CTB, plant-synthesized CTB dissociated into monomers (Mr 15 kDa) during heat or acid treatment. The maximum amount of CTB protein detected in auxin-induced transgenic potato leaf and tuber tissues was approximately 0.3% of total soluble plant protein. Enzyme-linked immunosorbent assay methods indicated that plant-synthesized CTB protein bound specifically to GM1-ganglioside, the natural membrane receptor of cholera toxin. In the presence of the SEKDEL signal, CTB protein accumulates in potato tissues and is assembled into an oligomeric form that retains native biochemical and immunological properties. The expression of oligomeric CTB protein with immunological and biochemical properties identical to native CTB protein in edible plants opens the way for preparation of inexpensive food plant-based oral vaccines for protection against cholera and other pathogens in endemic areas throughout the world  

番茄花叶病毒单克隆抗体的制备及检测应用

用番茄花叶病毒(ToMV)免疫的BAL B/c鼠脾细胞与SP2/0鼠骨髓瘤细胞融合，经筛选克隆，获得4株能稳定传代并分泌抗ToMV单克隆抗体(Mab)的杂交瘤细胞，其中2株能同时检测ToMV和烟草花叶病毒(TMV)，各单克隆抗体腹水ELLSA效价在1∶32 000～1∶1 024 000之间。经TASELISA测定，4株单克隆抗体检测病汁液的稀释度均能达到1∶2 000倍以上。4株单克隆抗体与其他病毒无交叉反应。Westernblot分析表明，其中两株与ToMV176kD的外壳蛋白亚基有特异反应，而另两株无反应，推测它们是针对构象决定簇的抗体。  

用ElISA研究稻田节肢类捕食者对稻飞虱的捕食作用

 应用酶联免疫吸附试验(ELlSA)来研究捕食作用能较准确地评价捕食性天敌对害虫的控制作用。ELlSA检测表明，不同种类的捕食性天敌对稻飞虱的捕食作用有较大差别，其中以优势种食虫沟瘤蛛和拟水狼蛛的捕食作用最大，阳性反应率与稻飞虱的种群密度有一定的相关关系，但在稻飞虱密度较低的情况下也表现出较高的阳性反应率。  

芜菁花叶病毒单克隆抗体的制备及检测应用

先以芜菁花叶病毒（TuMV）免疫BAL B/C小鼠，然后取其脾细胞使之与SP2/0鼠骨髓瘤细胞融合，经筛选、克隆，获得4株能稳定传代并分泌抗TuMV单克隆抗体（Mab）的杂交瘤细胞，并以之制备腹水单抗。4株单克隆抗体腹水ELISA效价在10-5～10-6之间，仅对TuMV起特异性反应。Western blot分析表明，4株单抗都能与TuMV 34kD的外壳蛋白亚基起特异反应。利用TuMV的多抗兔血清和单抗腹水建立了三抗体夹心ELISA检测TuMV的方法，检测病叶的灵敏度为1∶5120倍，检测提纯TuMV病毒绝对量为21.9 ng。利用三抗体夹心ELISA测定出7种作物上有TuMV侵染。   

Release of heart fatty acid-binding protein into plasma after acute myocardial infarction in man

The release of cytoplasmic heart fatty acid-binding protein (H-FABP) into the plasma of cardiac patients up to 38 hr after the onset of the first clinical symptoms of acute myocardial infarction (AMI) was studied, using a sensitive direct and noncompetitive Enzyme Linked Immunosorbent Assay of the antigen capture type (sandwich ELISA), newly developed for the measurement of small amounts of human H-FABP in plasma samples. Plasma levels of H-FABP were compared with plasma activity levels of the myocardial cytoplasmic enzymes creatine kinase MB (CK-MB) and alpha-hydroxybutyrate dehydrogenase (-HBDH). Upper normal levels of H-FABP (19g/l), CK-MB (10 U/l) and -HBDH (160 U/l) as determined in plasma from 72 blood donors served as threshold levels. H-FABP levels were significantly elevated above their threshold level within 3 hr after AMI. Peak levels of H-FABP, CK-MB and -HBDH were reached 4.1 ± 0.9 hr, 8.4 ± 1.4 hr and 25.0 ± 9.5 hr (means ± S.D., n = 10) after acute myocardial infarction, respectively. Serial time curves of the plasma contents of H-FABP reveal that after myocardial infarction H-FABP is released in substantial amounts from human hearts. In 18 out of 22 patients with established AMI the plasma FABP level was at or above the threshold level in blood-samples taken within 3.5 hr after the first onset of symptoms of AMI, while for CK-MB this applied to 9 patients and for -HBDH to 6 patients. These findings suggest that for an early indication of acute myocardial infarction in man cytoplasmic heart fatty acid-binding protein is more suitable than heart type creatine kinase MB and/or alpha-hydroxybutyrate dehydrogenase. (Mol Cell Biochem116: 155–162,1992)Abbreviations H-FABP (cytoplasmic) Heart Fatty Acid-Binding Protein - LDH Lactate Dehydrogenase, -HBDH--Hydroxybutyrate Dehydrogenase - CK-MB Creatine Kinase-MB - AMI Acute Myocardial Infarction - PBS Phosphate Buffered Saline - BSA Bovine Serum Albumin  

三种方法检测梅毒螺旋体抗体的比较

应用ELISA法、TRUST法和TPPA法分别检测梅毒患者血清标本中梅毒螺旋体IgG抗体,比较3种方法的敏感性和特异性,选择一种适合于梅毒螺旋体抗体检测的高敏感性和高特异性的血清学检测方法。  

植物组织粗汁液中的番木瓜环斑病毒的ELISA检测技术

本研究建立和改进了检测番木瓜和西葫芦组织粗汁液里的番木瓜环斑病毒（ＰＲＶ）的ＤＡＣ－ＥＬＩＳＡ法和Ｄｏｔ－ＥＬＩＳＡ法。用不同的ＥＬＩＳＡ方法来检测不同寄主植物粗汁液里的ＰＲＶ，其所用的合适的制备粗汁液的缓冲液是不同的。用ＤＡＣ－ＥＬＩＳＡ法检测西葫芦粗汁液时，以０．５ｍｏｌ／Ｌ磷酸盐缓冲液（ｐＨ７．５，内含０．１ｍｏｌ／Ｌ乙二胺四乙酸二钠）为宜；而检测番木瓜粗汁液时，则还要加入０．２５ｍｏｌ／Ｌ脲。用Ｄｏｔ－ＥＬＩＳＡ法检测时，在上述磷酸盐缓冲液中加入２％聚乙烯吡咯烷铜能提高对西葫芦粗汁液的检测效果。应用合适的制备粗汁液的缓冲液，ＤＡＣ－ＥＬＩＳＡ法和Ｄｏｔ－ＥＬＩＳＡ法的灵敏度分别提高到１／４０９６和１／１０２４（稀释度）。本研究还表明，影响ＤＡＣ－ＥＬＩＳＡ法的定过测定的主要因素是粗汁液的稀释度和包被液（０．０５ｍｏｌ／Ｌ碳酸盐缓冲液，ｐＨ９．６）的用过。在较高粗汁液稀释度和包被液的用量相同时，粗汁液里的病毒含量与ＤＡＣ－ＥＬＩＳＡ法的ＯＤ４９２ｎｍ值呈真实的线性关系。