多肽抗体检测原发性肝癌血清标志物ELISA方法的建立及应用

血清多肽是癌症诊断信息的重要来源,建立、优化了检测多肽标志物的直接ELISA法,并应用于肝癌血清中的多肽标志物的检测。制备及纯化针对多肽标志物Pep5的单克隆抗体并进行辣根过氧化物酶标记,用其建立检测相应抗原的直接ELISA法。方法线性范围为1.5-20 ng/mL,检测限为1.24 ng/mL;标准品批内及批间CV分别小于3.66%及4.89%,血清样本批内及批间CV分别小于11.69%及18.18%;线性范围内(9、12和15 ng/mL)的回收率分别为98.98%,99.61%和101.58%。应用该方法共检测160例正常血清、104例肝硬化及156例肝癌患者血清,正常组与肝硬化组及肝癌组间差异显著(P<0.001),Pep5诊断肝癌的敏感性和特异性分别为80.8%和96.2%。同时检测94例HCC血清中的AFP和Pep5,AFP检出率为63.8%,Pep5检出率为90.4%,AFP联合Pep5检测时,能将HCC的检出率提高至94.7%。     

运用ELISA快速检测CPV抗体方法的建立与均衡性研究

用蔗糖密度梯度离心和凝胶层析纯化犬细小病毒 (CPV)作抗原 ,建立了检测CPV抗体的间接酶联免疫吸附试验 (ELISA)法 ,其特异性和稳定性良好 ,结果判定准确明显 ,易于把握。     

利用竞争型ELISA法鉴定硒诱导的金属硫蛋白

利用竞争型ELISA法鉴定硒诱导的金属硫蛋白 (MT) ,发现对照组小鼠肝脏MT含量为 (2 .47± 0 .90 )μg/g湿重组织 ,硫酸锌组小鼠肝脏MT含量为 (8.15± 2 .2 0 ) μg/ g湿重组织 ,硒麦芽组小鼠肝脏MT含量为(12 .80± 1.44 ) μg/ g湿重组织。锌组和硒组的MT含量与对照组相比有显著性差异 (P <0 .0 5 ,P <0 .0 5 )。硒组MT含量要显著高于锌组的MT含量 (P <0 .0 5 )。     

The wall associated lipoteichoic acid ofStreptococcus sanguis

A competitive ELISA is described for the measurement of lipoteichoic acid. The assay was used to determine the wall associated lipoteichoic acid ofStreptococcus sanguis which was found to represent only 2–4% of the phenol extractable content. Extracellular lipoteichoic acid was detected even after exhaustive cell washing. This material was not the result ofde novo synthesis because membrane de-polarization had no effect on the amount detected. Since extracellular lipoteichoic acid interfered with the measurement of cell surface antigen, cells were fixed with glutaraldehyde prior to assay. Lipoteichoic acid was demonstrated on the surface of fixed cells which did not leak antigen. The relevance of fixation used in antigen location studies by electron microscopy of immune-labelled cells is discussed.     

TT病毒重组蛋白单克隆抗体的制备

采用杂交瘤技术,获得了4株稳定分泌抗TTV重组蛋白的单克隆抗体杂交瘤细胞株,1株属IgG2bλ链、1株属IgG1κ链、2株属IgG2aκ链。4株杂交瘤细胞培养上清液效价为1：80-1：1280,腹水效价为1：32万-1：160万。     

ELISA技术筛选200种中草药抗HBsAg的实验研究

使用ＥＬＩＳＡ技术对２００种中草药水提取物进行抗ＨＢｓＡｇ的实验研究,共筛出有效药物７种（占总数的３．５％）。若按５种不同剂量（０．３、０．６、１．２、２．５、５．０ｍｇ／１００μｌ）的药物、２种不同浓度的ＨＢｓＡｇ（１０．９２、１４．２６Ｐ／Ｎ值）与３种不同接触时间（立即、１ｈ、２ｈ）的１０项Ｐ／Ｎ值均数来综合评价药效指数时,７种有效药物的次序为青蒿（１．６７Ｐ／Ｎ值）、大蒜（２．１９Ｐ／Ｎ值）、红孩儿（２．３１Ｐ／Ｎ值）、仙鹤草（２．３１）、魔芋（２．３２Ｐ／Ｎ值）、冬瓜皮（２．６３Ｐ／Ｎ值）和猕猴桃（２．８９Ｐ／Ｎ值）。     

Expression of Recombinant Extracellular Domain of the Type II Transforming Growth Factor-β Receptor: Utilization in a Modified Enzyme-Linked Immunoabsorbent Assay to Screen TGF-β Agonists and Antagonists

TGF-β is a ubiquitous protein that exhibits a broad spectrum of biological activity. The prokaryotic expression and purification of the extracellular domain of the type II TGF-β receptor (TβR-II-ED), without the need for fusion protein cleavage and refolding, is described. The recombinant TβR-II-ED fusion protein bound commercially available TGF-β1 and displayed an affinity of 11.1 nM. In a modified ELISA, receptor binding to TGF-β1 was inhibited by TGF-β3. The technique lends itself to high-throughput screening of combinatorial libraries for the identification of TGF-β agonists and antagonists and this, in turn, may have important therapeutic implications.     

Whole-cell antigens of members of the sulfate-reducing genus Desulfovibrio

Antisera have been developed against the wholecell antigens of Desulfovibrio africanus Benghazi and Walvis Bay, D. vulgaris Hildenborough, D. salexigens British Guiana, D. gigas, and D. desulfuricans Essex 6. An enzymelinked immunoadsorption assay (ELISA) was developed to measure the reaction of these antisera with the homologous and heterologous antigens. The ELISA method demonstrated a reaction between pre-immune sera and cells of D. africanus, D. gigas and D. desulfuricans, suggesting the presence of a lectin-like substance on these cell surfaces. Extensive cross-reactions were seen between the antisera and heterologous cells, suggesting the sharing of a number of surface antigens amongst the Desulfovibrio. However, the pattern of these cross-reactions was different from that observed for an ELISA reaction developed for the cytochrome c₃ from various Desulfovibrio.Abbreviation ELISA enzyme-linked immunoadsorption assay     

B Cell Epitopes within VP1 of Type O Foot-and-mouth Disease Virus for Detection of Viral Antibodies

In this study,the coding region of type O FMDV capsid protein VP1 and a series of codon optimized DNA sequences coding for VP1 amino acid residues 141-160(epitope1),tandem repeat 200-213(epitope2(+2)) and the combination of two epitopes(epitope1-2)was genetically cloned into the prokaryotic expression vector pPROExHTb and pGEX4T-1,respectively.VP1 and the fused epitopes GST-E1,GST-E2(+2)and GST-E1-2 were successfully solubly expressed in the cytoplasm of Escherichia coli and Western blot analysis demonstrat...