Application of an immunological method to detect trace amounts of dried human semen

An immunological assay based on a monoclonal antibody was used for identification of trace amounts of dried human semen in forensic science evidence. The monoclonal antibody (Mab 4E6) produced recognizes a human sperm-coating antigen which is specific to human seminal plasma. This antigen seems to be a protein secreted by the epithelial cells of the ejaculatory duct, which is stable indefinitely at room temperature. Mab 4E6 reacts positively with semen samples from individuals independently to their ABO group or secretory status, but does not react with semen from bull, ram, boar, horse, rabbit and dog. In the assay system developed, Mab 4E6 can detect human seminal plasma at concentrations of 0.5 micrograms/ml total protein. A similar sensitivity is found when human semen stains are eluted from forensic science samples and tested by the same assay. This method shows a good correlation with the microscopic methods routinely used. The method described is very sensitive and reproducible, it is time saving and special laboratory equipment is not needed.     

鼠抗人转铁蛋白单链抗体基因的表达

目的 制备抗人转铁蛋白单链抗体。方法 拼装好并带有酶切位点粘性末端的鼠抗人转铁蛋白的单链抗体基因经凝胶电泳定量后,同载体pCANTAB 5E连接,以其转化E.coli TG1细胞,经辅助噬菌体M13K07挽救构建噬菌体抗体表面呈现文库、抗原包被固相材料富集选择阳性重组噬菌体克隆（Panning）。感染能产生可溶抗体片段的大肠杆菌菌株E.coli HB2151,制备可溶抗体,以Anti-E末端抗体进行Western blot、ELISA检验和分子量测定。结果 人转铁蛋白的单链抗体基因成功表达。结论 用基因工程抗体技术制备抗体是可行的。     

用ELISA检测精液及精斑中精子抗原的研究

本实验应用单克隆抗人精子抗体和酶标记羊抗人精子抗体,采用ELISA方法确定精子抗原成份的存在。对10份新鲜精液,15份精斑进行了验测,其结果阳性率为100%。新鲜精液(精子数约10,000万个/ml)稀释100万倍,精斑浸出液稀释50万倍,均可出现阳性。对唾液斑、尿斑、乳汁斑、阴道斑、汗斑及输精管结扎的精液均为阴性。实验结果表明,本法检验精子抗原具有灵敏度高,特异性好的优点。     

抗丁丙诺啡单克隆抗体的制备

目的建立抗丁丙诺啡单克隆抗体的杂交瘤细胞株，制备高特异性的丁丙诺啡单克隆抗体，并对其免疫学特性进行鉴定。方法在丁丙诺啡的分子上连接活性羧基基团，通过缩合反应将丁丙诺啡半抗原连接于血蓝蛋白（KLH）和小牛血清白蛋白（BSA），形成完全抗原。以完全抗原免疫Balb／c小鼠，通过细胞融合，筛选等杂交瘤技术，建立稳定的分泌抗丁丙诺啡单克隆抗体的杂交瘤细胞株。通过腹腔注射杂交瘤细胞，诱导小鼠产生含有单抗的腹水。用辛酸-硫酸铵加亲和层析法纯化抗丁丙诺啡单克隆抗体。采用酶联免疫反应和胶体金膜层析实验测定丁丙诺啡单抗的特异性以及免疫反应动力学参数。结果共获得3株分泌抗丁丙诺啡单克隆抗体的杂交瘤细胞株，分别命名为7E6，6G4和3C2。7E6，6G4抗体灵敏度为10．0ng／ml，3C2抗体灵敏度为20．0ng／ml。7E6，6CA和3C2抗体的亲和常数分别为3．6×10^-9 mol／L，4．3×10^-9 mol／L和6．3×10^-9 mol／L。特异性测试结果表明7E6和6G4抗体与40种药物、毒品无任何交叉反应，而3C2抗体与吗啡有交叉反应。结论杂交瘤细胞株7E6和6G4产生的抗丁丙诺啡单克隆抗体具有很高的特异性和灵敏度。     

Enzyme-linked immunosorbent assay and latex agglutination inhibition reaction test for cocaine and benzoylecgonine in urine

An enzyme-linked immunosorbent assay (ELISA) and a latex agglutination inhibition reaction test (LAIRT) for cocaine and benzoylecgonine have been established. In ELISA with polystyrene microtiter wells coated with anti-benzoylecgonine antibody and alkaline phosphatase (ALP)-labeled benzoylecgonine, the activity of antibody-bound ALP was measured with the enzyme cycling method. The range of benzoylecgonine measurable by ELISA was 12 pg-25 ng/well; the analysis time for 96 wells was 90 min. In LAIRT, the agglutination reaction with anti-benzoylecgonine antibody-coated latex and benzoylecgonine-rabbit serum albumin (RSA) conjugate-coated latex was inhibited by 0.1 μg benzoylecgonine/ml urine; the analysis time for six samples on one glass slide was 20 min. The urine samples of 47 abusers were analyzed by ELISA and LAIRT. From the comparison with results of the enzyme-multiplied immunoassay technique (EMIT^®) and gas chromatography-mass spectrometry (GC-MS), it was clarified that both ELISA and LAIRT were suitable for the screening method of urine samples.     

An enzyme-linked immunosorbent assay (ELISA) for human semen identification based on a biotinylated monoclonal antibody to a seminal vesicle-specific antigen

Monoclonal antibody mouse antihuman semen-5 (MHS-5) (immunoglobulin G1 [IgG1]) was biotinylated using N-biotinyl-w-aminocaproic acid-N-hydroxysuccinimide ester. This monoclonal antibody-biotin conjugate recognized low molecular weight peptide bands between 10.5 and 20 kilodaltons on immunoblots of liquefied semen. Immunodominant peptides had molecular weights of 10.5, 11.5, and 13.5 kilodaltons. An enzyme-linked immunosorbent assay (ELISA) developed with the biotinylated-MAb and streptavidin peroxidase demonstrated sensitivity curves with lower limits of 10 ng of seminal fluid protein per microtiter well using 50 ng per well of monoclonal antibody-biotin conjugate. Cross-reactivity studies on a panel of human biological fluids and tissues demonstrated no cross-reactivity or false positives using the monoclonal antibody-biotin conjugate. The sensitivity of the monoclonal antibody-biotin ELISA was compared to ELISA based upon a polyclonal secondary antibody-peroxidase conjugate. These findings indicate that this ELISA assay, based on a biotinylated monoclonal antibody to a seminal vesicle-specific antigen, may be useful for semen identification.     

A sandwich enzyme immunoassay for human pancreatic elastase III

To develop a method for the determination of pancreas injuries using a pancreas-specific antigen as a marker, human elastase III was purified from the pancreas by chromatographic methods. A rabbit anti-human elastase III antibody was prepared, and this antibody was confirmed using immunoblotting to react only with elastase III among proteins from the pancreas. A sensitive sandwich enzyme immunoassay for human elastase III was developed. The detection limit for human elastase III was 0.3 pg (10 amol) per assay. Proteins extracted from the pancreas showed the strongest response, whereas reactions of the other organs were less than the detection limit. These results suggest that a sandwich enzyme immunoassay for human elastase III is useful for the determination of pancreas injury.     

Immunoassay for methamphetamine with a new antibody

p- and o-Aminomethamphetamine were synthesized as haptens to be coupled with carrier protein at the benzene ring of methamphetamine. Immunogens were prepared by the glutaraldehyde method or the MBS (N-(m-maleimidobenzoyloxy)succinimide) type cross-linking reagent method. In particular, immunization with p-aminomethamphetamine-bovine serum albumin (BSA) conjugate prepared by the glutaraldehyde method gave an anti-methamphetamine antiserum having a low cross-reactivity with methylephedrine. With the antiserum, three kinds of immunoassays for methamphetamine were established. An enzyme immunoassay (EIA) and an enzyme-linked immunosorbent assay (ELISA) were developed with alkaline phosphatase (ALP) as a label enzyme. The amount of antibody bound ALP conjugate was determined by its activity in dephosphorylating p-nitrophenyl phosphate in EIA and nicotinamide adenine dinucleotide phosphate (NADP+) in ELISA. The range of methamphetamine measurable by ELISA was 0.025-0.5 ng/well and its sensitivity was superior to that of EIA (0.3-300 ng/tube). A latex agglutination inhibition reaction test (LAIRT) was also developed for the mass screening method of urine samples. The sensitivity of this method for methamphetamine was 0.1 micrograms/ml urine.     

Interpretations of the TDxFLx calibration data of the abused drugs

The useful TDxFLx calibration data was obtained for the interpretation of the interactions of the abused drugs to sheep antiserum protein. The antibody of TDxFLx calibrators was prepared from sheep antiserum. Furthermore these data can be used to interpret the abused drug-protein binding phenomena in human body and the TDxFLx screening results of the abused drugs in urine samples. TDxFLx system uses fluorescence polarization immunoassay technique that is a competitive binding immunoassay methodology to allow tracer-labeled antigen (*Drug) and patient antigen (Drug) to compete for the same binding sites on the antibody molecules of sheep antiserum. To obtain the binding parameters, binding constant (K) and number of independent binding site (n), generally, Scatchard equation is used. This Scatchard equation is expressed in the concentration terms of free drug, bound drug, and protein (antibody). The binding parameters can not be obtained by applying the TDxFLx calibration data to the Scatchard equation directly because the TDxFLx calibration data are composed of the fluorescence polarization and the total drug concentrations. To obtain the binding parameters from the TDxFLx calibration data the new useful equation which was expressed in the total concentrations of drug and fluorescence polarization should be derived. Derivation of new equation was based on the Scatchard equation. The TDxFLx calibration data was curve fitted to the derived equation using KaleidaGraph program and Macintosh computer. The binding constant (K) and the number (n(P(t))) of binding site of 11-nor-delta(9)-tetrahydrocannabinol-9-carboxylic acid (COOH.THC) on the antibody were 1.14 x 10(8)l/mole and 4.04 x 10(-7)M, respectively. The binding constant and the number (n(P(t))) of binding site of amphetamine were 5.15 x 10(5)l/mole and 2.05 x 10(6)M, respectively. In case of COOH.THC the fluorescence polarization decreased linearly with the concentration. However, in case of amphetamine or the other three abused drugs the fluorescence polarizations decreased exponentially with their concentrations.     

Evaluation of the One-Step ELISA kit for the detection of buprenorphine in urine, blood, and hair specimens

A solid-phase enzyme immunoassay involving microtiter plates was recently proposed by International Diagnostic Systems corporation (IDS) to screen for buprenorphine in human serum. The performance of the kit led us to investigate its applicability in other biological matrices such as urine or blood, and also hair specimens. Low concentrations of buprenorphine were detected with the ELISA test and confirmed by HPLC/MS (buprenorphine concentrations measured by HPLC/MS: 0.3 ng/mL in urine, 0.2 ng/mL in blood, and 40 pg/mg in hair). The intra-assay precision values were 8.7% at 1 ng/mL of urine (n = 8), 11.5% at 2 ng/mL in serum (n = 8), and 11.5% at 250 pg/mg of hair (n = 8), respectively. The immunoassay had no cross-reactivity with dihydrocodeine, ethylmorphine, 6-monoacetylmorphine, pholcodine, propoxyphene, dextromoramide, dextrometorphan at 1 and 10 mg/L, or codeine, morphine, methadone, and its metabolite EDDP. A 1% cross-reactivity was measured for a norbuprenorphine concentration of 50 ng/mL. Finally, the immunoassay was validated by comparing authentic specimens results with those of a validated HPLC/MS method. From the 136 urine samples tested, 93 were positive (68.4%) after the ELISA screening test (cutoff: 0.5 ng/mL) and confirmed by HPLC/MS (buprenorphine concentrations: 0.3-2036 ng/mL). From the 108 blood or serum samples screened, 27 were positive (25%) after the ELISA test with a cutoff value of 0.5 ng/mL (buprenorphine concentrations: 0.2-13.3 ng/mL). Eighteen hair specimens were positive (72%) after the screening (cutoff: 10 pg/mg) and confirmed by LC/MS (buprenorphine concentrations: 40-360 pg/mg). The ELISA method produced false positive results in less than 21% of the cases, but no false negative results were observed with the immunological test. Four potential adulterants (hypochloride 50 mL/L, sodium nitrite 50 g/L, liquid soap 50 mL/L, and sodium chloride 50 g/L) that were added to 10 positive urine specimens (buprenorphine concentrations in the range 5.3-15.6 ng/mL), did not cause a false negative response by the immunoassay.     

Validity testing of commercial urine cocaine metabolite assays: III. Evaluation of an enzyme-linked immunosorbent assay (ELISA) for detection of cocaine and cocaine metabolite

A validity assessment study was performed on the Genetic Diagnostic Enzyme Immunoassay test kit, a new enzyme-linked immunosorbent assay (GDC ELISA) for detection of cocaine and cocaine metabolite in urine. A set of 290 urine specimens, comprised of clinical cocaine urines collected from 5 male subjects who had received single doses of intravenous cocaine, drug-free urines spiked with cocaine, cocaine metabolites, cocaine isomers, and other drugs of abuse, were assayed by GDC ELISA. The results were compared with results by gas chromatography/mass spectrometry (GC/MS) assay for benzoylecgonine. Concordance was high between the GDC ELISA assay and GC/MS and with results reported earlier for other commercial assays. Detection times and specificity of the GDC ELISA antibody were most similar to those of the Abuscreen radioimmunoassay for cocaine metabolite. Overall, the assay produced no false negative or false positive results and appeared to be a reliable screening test for detection of cocaine and benzoylecgonine in human urine.     

Screening postmortem whole blood for oxycodone by ELISA response ratios

The objective of this study was to investigate the accuracy of screening postmortem whole blood for oxycodone using the ratio of the oxycodone immunoassay response to the response for the specimen obtained with a general opiate-class immunoassay. Fifty eight specimens which were negative for opiates and 158 postmortem whole blood specimens positive for opiates including 66 specimens known to contain oxycodone were assayed. Specimens were diluted 1:5 with assay buffer and analyzed by both the Neogen Oxymorphone/Oxycodone ELISA and the Neogen Opiate Group ELISA (Neogen Corporation, Lexington KY). The oxycodone equivalents in ng/mL from the Oxymorphone/Oxycodone ELISA were divided by the morphine equivalents in ng/mL from the Opiates ELISA to obtain an Oxycodone/Opiates Response Ratio. This ratio was compared with the GC/MS data for all specimens and for opiate positive specimens. Receiver Operating Characteristic (ROC) analysis suggested that optimum relative response ratio was 2.0. The sensitivity of the ELISA response ratio for the presence of oxycodone at a response ratio cutoff of 2.0 was 89.4% +/- 3.8% and the specificity was 88.1% +/- 3.2%. Specimens with a ratio of 2.0 or higher had a greater than 50% probability (positive predictive value) of containing oxycodone in a population with a greater than 15% prevalence of oxycodone.     

Detection of Lea substance in saliva stains by enzyme-linked immunosorbent assay (ELISA) using anti-gum arabic serum

It is known that rabbit anti-gum arabic (GA) serum has cross-reactivity with Lea antigen, and that, by using this cross-reactive anti-Lea antibody, the presence of Lea antigen in red blood cells and saliva can be demonstrated with accuracy. We have devised a rapid and highly sensitive method for detecting Lea substance in human saliva by the enzyme-linked immunosorbent assay (ELISA) method using an anti-Lea antibody isolated from anti-GA serum by affinity chromatography on Synsorb Lea. The ELISA plate, coated with the specific anti-Lea antibody, adsorbed the Lea substance in saliva which was subsequently identified by adding enzyme labeled anti-Lea IgG in that order. The method could detect the Lea substance in Le(a+) saliva stains as small as 0.1 by 0.1 cm in size that had been stored at room temperature for three weeks and in Le(a+) saliva stains 0.7 by 0.7 cm in size that had been stored for ten years. This method seems to be useful for quantitative analyses of the Lea substance in various body fluids.     

An enzyme immunoassay for prostate-specific p30 antigen detection in the postcoital vaginal tract

A sandwich enzyme immunoassay test utilising a mouse monoclonal antibody has been adapted for the sensitive detection of the p30 prostatic antigen in semen and in postcoital vaginal swabs. In liquid semen, p30 was still detectable at a 1/1,000,000 dilution, and it could still be detected on vaginal swabs 24 h postcoitus.     

Evaluation of two immunoassay procedures for drug testing in hair samples

A preliminary initial enzyme-linked immunosorbent assay (LUCIO-Direct ELISA kit) and a preliminary DRI enzyme immunoassay were evaluated for drug detection in head hair with respect to lowered cutoff values recommended in Germany for the control of abstinence in cases of re-granting of drivers' licences. Following drug classes were included: cannabinoids, opiates, cocaine like substances, amphetamine, methamphetamine (and methylenedioxyamphetamines), methadone, and benzodiazepines. 759 analyses were performed using LUCIO-Direct ELISA kits and 936 analyses using DRI enzyme immunoassay tests. Sample size for each drug group and immunoassay test reached from 74 to 178. The LUCIO-Direct ELISA kit revealed a sensitivity of 91% for amphetamine up to 98% for methadone (methamphetamine 92%, cocaine 94%, opiates 94%, benzodiazepines 96%) and values of specificity of 72% for methadone up to 89% for amphetamine and benzodiazepines. The test was not useful for a preliminary screening for tetrahydrocannabinol (sensitivity of 65%) in consideration of a suggested cutoff of 0.02 ng/mg. The DRI enzyme immunoassay test was only useful for morphine and cocaine testing at low recommended new cutoff values (0.1 ng/mg) revealing sensitivities of 94% and 99%, respectively.     

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.     

Gm typing by enzyme-linked immunosorbent assay (ELISA)

A solid-phase ELISA for Gm typing is described. A mixture of anti-Gm serum (or monoclonal anti-Gm antibody) and test serum was incubated in microtiter wells coated with IgG or its fragments of appropriate Gm type. After washing of the wells, the bound antibody was detected with peroxidase-labeled second antibody. The Glm(3), G3m(16), and G3m(21) antigens could be identified by this technique. Since some of the human anti-Gm sera and anti-Rh0 sera required for the conventional hemagglutination-inhibition method are hard to obtain, the ELISA system using anti-Gm antibodies and no anti-Rh0 sera may serve as an alternative to the conventional method.     

Screening and confirmation of drugs in urine: interference of hordenine with the immunoassays and thin layer chromatography methods.

Hordenine cross-reacted with various enzyme linked immunosorbent assay (ELISA) or radioimmunoassay (RIA) kits used for the screening of urine samples. Morphine-ELISA kit was most sensitive, whereas etorphine- and buprenorphine-ELISA kits were least sensitive to hordenine cross-reactivity. Hordenine also interfered with the thin layer chromatography of oxymorphone, hydromorphone and apomorphine. The major source of hordenine in humans is beer brewed from barley, whereas the major source of hordenine in horses is canary grass or barley. Therefore, the presence of hordenine in the urine of humans consuming beer or in the urine of horses consuming canary grass may give false positive values when the immunoassay and TLC methods are used for the screening of the urine sample. In order to distinguish hordenine from the opiate drugs, simple and sensitive gas chromatographic/mass spectrometric (GC/MS) and high performance liquid chromatographic (HPLC) methods have been developed in this study.     

检测丁丙诺啡的胶体金标记单克隆抗体免疫试剂盒研制

目的采用免疫竞争法原理,建立一种简便快速检测丁丙诺啡的方法。方法将20nm胶体金颗粒标记的抗丁丙诺啡单克隆抗体,均匀浸在吸水玻璃纤维上,将丁丙诺啡-BSA和纯化后的羊抗鼠IgG多克隆抗体在硝酸纤维薄膜分别划1mm宽的检测线(T线)和质控线(C线),制成丁丙诺啡胶体金标记单克隆抗体免疫层析检测条,并组装成检测板。结果以GC/MS为标准对照,100例样品检测结果显示,本检测板的准确率为99.0%。丁丙诺啡胶体金标记单克隆抗体免疫层析检测板在对45种药(毒)物的测试中,仅识别丁丙诺啡及其主要代谢产物。结论丁丙诺啡胶体金标记单克隆抗体免疫层析检测板在5min内可检出样品中的丁丙诺啡及其代谢物,检测丁丙诺啡的阈值为100ng/mL。     

SMCY性别特异融合抗原的克隆表达及其抗体制备

目的利用蛋白检测的快速性优势,研究不同性别在SMCY抗原氨基酸序列的差异,筛选出特异性氨基酸序列,并克隆表达性别特异融合抗原,制备相应抗体,建立一种快速鉴别法医物证性别的方法。方法通过对人SMCY和SMCX进行序列分析,发现了三段差异片段,采用搭桥PCR方法获得差异片段全长基因,连接入p ET-28a载体进行原核表达,用Ni柱纯化后的性别特异融合抗原免疫制备多克隆抗体,用ELISA法和western blot检测SMCY多抗与抗原的反应特异性,制作胶体金试纸条检测样本。结果筛选出具有性别特异性的氨基酸序列,获得SMCY性别特异融合抗原,成功制备出多克隆抗体及胶体金试纸条。结论获得SMCY性别特异融合抗原具有很好的抗原活性,制备的多克隆抗体可以与抗原特异性地结合,用于性别鉴定。