Western blot assay for prostate-specific membrane antigen in serum of prostate cancer patients

There is a need for the development of new diagnostic tools for the early detection of prostate cancer. A candidate molecule for a new screening test is a prostate-specific membrane antigen (PSM) recognized by the monoclonal antibody 7E11.C5. We carried out studies aimed at identifying PSM in the serum of normal and benign prostatic hyperplasia (BPH) donors and patients with adenocarcinoma of the prostate, in order to judge whether the development of a serum assay using this marker was feasible. By Western blotting, we found significant levels of PSM in serum samples from prostatic cancer patients, in the seminal fluid of pooled normal donors, in BPH patients, and in normal male sera. Similar to prostate-specific antigen (PSA), PSM was present in seminal plasma in higher concentrations than in serum, and PSM levels in prostatic cancer patients were significantly higher than in normal controls. These data suggest that the development of an assay utilizing the PSM and new monoclonal antibodies directed against the antigen, could provide a feasible test for prostatic cancers. © 1994 Wiley-Liss, Inc.     

Antibodies toMycobacterium paratuberculosis in patients with Crohn's disease

IgG antibodies againstMycobacterium paratuberculosis protoplasmic antigen were looked for by an enzyme immunosorbent assay in patients with Crohn's disease, Ulcerative colitis, active pulmonary tuberculosis, past pulmonary tuberculosis, and in healthy controls. Serum reactivity for these antibodies was not correlated to PPD skin test positivity without history of mycobacterial disease. A cutoff based on the mean absorbance value of a pool of healthy blood donors was chosen. Positive values were found in 12/24 (50%) patients with active pulmonary tuberculosis and 2/10 (20%) skin-test-positive subjects with past pulmonary tuberculosis as expected, because antigenic sharing is common among different mycobacteria. The control group of blood donors showed borderline positivities in 3/149 cases (2.01%). Positive values were found in 4/108 (3.70%) patients with Crohn's disease and 2/40 (5%) with ulcerative colitis. We conclude that our data do not support a causal relationship between theM. paratuberculosis and Crohn's disease, but occasional patients with inflammatory bowel diseases show unexpected positivities for these mycobacterial antibodies.     

Identification of a differentially expressed Echinococcus multilocularis protein Em6 potentially related to antigen 5 of Echinococcus granulosus

By a strategy of differential immunological screening of an expression library constructed from adult Echinococcus multilocularis parasites, a partial cDNA sequence encoding a protein termed Em6 was isolated. This molecule displayed high sequence homology to the recombinant antigen 'Eg6' which was previously described as an immunogenic epitope of antigen 5 of E. granulosus. Further Em6 sequences and the corresponding sequences from a cattle isolate of E. granulosus were obtained by a PCR approach. By immunoblot analyses using affinity purified antibodies, expression of Em6 in fertile cysts producing protoscoleces of the E. multilocularis metacestode stage was observed. However, Em6 was absent in non-fertile metacestodes. The demonstration of a protein in E. multilocularis displaying identities to 'antigen 6' of E. granulosus could potentially contribute to the future elucidation of the relationship between antigen 5 and 'antigen 6' in the genus Echinococcus , and shed some lights on the performance of serodiagnostic assays for hydatid disease based on the respective antigens .     

血凝抑制试验对流行性出血热血清学诊断价值

应用血凝抑制试验（HI）检测169份流行性出血热病人血清，并与间接免疫荧光抗体（IFA）、反向被动凝集试验（RPHA）比较。三种方法的检测结果一致（X1^2=13.91,X2^2=31.85,X3^2=15.81),HI试验表明，它既可用于疾病的早期诊断，又可作为抗体分型，还可进行流行病学监测。     

A comparison between a new serological method, thin layer immunoassay (TIA), and the enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies in schistosomiasis

A comparison has been made of a new serological method, thin layer immunoassay (TIA), and an established method, enzyme-linked immunosorbent assay (ELISA), in the detection and quantification of antibodies in schistosomiasis. Using sera from known S. haematobium and S. mansoni cases, the performance of the two tests was almost identical; 95.6% positive for TIA and 96.4% by ELISA. TIA however produced a small number of false positives with sera from other helminth infections whereas ELISA gave none. There was excellent correlation between the tests in the quantification of anti-S. haematobium antibodies, both in human cases and in infected baboons. TIA has the advantage of being extremely simple to perform, but has the disadvantage of requiring a higher concentration of antigens.     

Serodiagnostik der Candida-Infektionen/Serological Diagnosis of Candida Infections

Zusammenfassung: Der Bericht bezieht sich auf serologische Untersuchungen an 4223 Patienten. Die Ergebnisse von Komplementbindungsreaktion (KBR), indirektem Hämagglutinationstest (HAT) und Immunelektrophorese (IE) mit metabolischem und somatischem Antigen werden beschrieben. Pathognomonische Titer nach einem negativen Ergebnis sind nach ein bis vier Wochen zu erwarten. Die positiven Befunde persistieren in der Regel nicht, sondern nähern sich relativ rasch dem Normalbereich. Nach ein bis acht Wochen ist wieder mit negativen Befunden zu rechnen. Ein erneuter Anstieg des Titers oder der Anzahl der Banden kann eine erneute Bedrohung durch Candida anzeigen. KBR und HAT erreichen im Durchschnitt wesentlich früher ihren Maximalwert als die Immunelektrophorese (p <0,001). Im chi-Quadrat-Test auf Unabhängigkeit ergaben sich zwischen jeweils zwei Testen p-Werte unter 0,0001. Die heuristische Konfigurationsfrequenzanalyse liefert Hinweise auf das Vorliegen von Typen und Anti-Typen in der Candidaserologie. Eine Empfehlung bezüglich der Untersuchungshäufigkeit und des sinnvollen Einsatzes der einzelnen Methoden wird erarbeitet. Summary: Serum samples from 4223 patients were examined for the presence of antibodies to Candida albicans. Serological findings obtained by complement fixation reaction (CFR), indirect hemagglutination test (IHT) and Immunoelectrophoresis (IE) against cytoplasmatic extracts and oidiomycin were evaluated. Pathognomonic titers can be expected one to four weeks after normal findings. Elevated titers usually do not persist. A decrease in antibody levels from initially high titers to insignificant range is found after one to eight weeks. Antibody levels rising again are considered diagnostically significant. CFR and IHT in general require less time to develop their peak value than immunoelectrophoresis (p <0.001). Chi-square tests for independence in 2 × 2-contingency tables reveal values of p <0.0001. The heuristic configural frequency analysis is used as a statistical tool for defining types in Candida serology. Types are defined as patterns of laboratory findings occuring more frequently than may be expected under the assumption of complete independence of the respective tests. Single determinations are inconclusive; use and value of serologic tests, particulary when used in combination and repeatedly, are discussed.     

Komparative klinisch-serologische Untersuchungen humoraler Candida-Antikörper mit der indirekten Immunfluoreszenz und der Mikroimmundiffusion*/Comparative Clinical-Serological Examinations of Humoral Antibodies against Candida albicans with the Indirect Immunofluorescence and the Double Immunodiffusion

Zusammenfassung: Bei 723 Seren von 62 Gesunden und 514 Patienten eines dermatologischen Krankengutes wurde die Präsenz humoraler Candida-Antikörper mit der indirekten Candida-Immunfluoreszenz (C-IF) und der radialen Doppeldiffusionstechnik nach Ouchterlony in der Mikromodifikation auf Objektträgern (DD) untersucht. Unter Zugrundelegung eines Grenztiters der C-IF von 1: 256 korrelieren die Befunde beider Methoden in 84, 2%. Bei Seren, die mit der C-IF Titer von 1: 256, 1: 512 und 1: 1024 aufweisen, erfolgt der Übergang von negativen zu positiven DD-Befunden. Demzufolge besteht in diesen drei Verdünnungsstufen die größte Diskrepanz zwischen den Ergebnissen beider Methoden. Negative Seren mit IF-Titern im Normalbereich von 1: 16 bis 1: 128 und positive Seren von 1: 2048 bis 1: 32768 korrelieren in 97,3% mit den Befunden der DD. Die DD beweist in unseren Untersuchungen eine hohe Spezifität, jedoch ist diese mit einer geringeren Sensitivität im unteren Grenzbereich pathologischer IF-Titer (1:512, 1:1024) gekoppelt, so daß Candidamykosen mit schwacher Antikörper-Produktion in 7,9% bis 17,4% ausgewählter Patientenkollektive nicht erfaßt wurden. Der Vorteil der C-IF liegt in der höheren Empfindlichkeit und der Möglichkeit zur Kontrolle der Titerdynamik im Krankheitsverlauf. Beide Methoden ergänzen sich sinnvoll und sollten zum Standardprogramm der serologischen Candida-Diagnostik gehören. Summary: 723 sera from 62 healthy persons and from 514 dermatological patients were examined for the presence of humoral antibodies against Candida albicans using the indirect Candida immunofluorescence test (C-IF) and the radial double diffusion technique after Ouchterlony in its micromodification on slides (DD). On the basics of a C-IF titer of 1: 256 as upper limit of the normal, the findings of both the methods correlate in 84.2%. In sera with C-IF titres of 1:256, 1: 512, and 1: 1024, the transition from negative to positive DD-findings takes place. Consequently, the greatest discrepancies between results of the two methods are found in these three steps of dilution. Sera having IF-titres within the normal range of 1: 16 up to 1: 128 and positive sera of 1: 2048 up to 1: 32768 correlate in 97.3% with the findings of the DD. In our examinations the DD proved to be highly specific in combination with a reduced sensitivity in the lower ranges of pathological IF-titres, thus causing false negative results in candidoses with limited antibody production. This was shown in 7.9% up to 17.4% of selected collectives of patients. The advantage of the C-IF is given by its higher sensitivity and by its applicability in controling titre dynamics during the course of the disease. The two methods are complementary in their diagnostic use and, therefore, should both belong to the serological standard programme in the diagnosis of candidoses.     

梅毒螺旋体不同血清学检验方法的应用评价

目的评价酶联免疫吸附试验（ELISA）、梅毒螺旋体明胶颗粒凝集试验（TPPA）和环状卡片快速血浆反应素试验（RPR）对梅毒病人诊断的敏感性和特异性。方法使用目前最为常用的梅毒螺旋体感染诊断ELISA和TPPA及RPR试剂对60例梅毒病人血清进行检测。结果ELISA法的阳性率96．67％，TPPA法阳性率98．33％，RPR法66．67％。结论ELISA法是一种高特异性，高敏感性的梅毒血清学诊断检测方法。     

双抗原夹心ELISA法检测抗念珠菌烯醇化酶抗体

目的建立检测抗念珠菌烯醇化酶(Eno)特异性抗体的双抗原夹心ELISA法,并进行临床应用评价。方法用基因工程制备的重组Eno作为包被抗原和酶标抗原,通过棋盘滴定法对双抗原夹心ELISA法的反应条件进行优化,对方法的敏感性、特异性和精密度进行考察。用双抗原夹心ELISA法测定291例住院患者(侵袭性念珠菌病114例,念珠菌定植82例,细菌感染患者95例)以及200名健康人血清,并与本实验室前期自建的间接ELISA法检测抗Eno抗体的结果进行比较。结果双抗原夹心ELISA法工作条件为:Eno抗原包被浓度为0.5μg/m L,酶标抗原1∶4 000稀释;封闭液为含50 g/L脱脂奶粉的PBS-T,待测血清稀释度为1∶100。患者血清检测结果显示,批内变异系数(CV)分别为6.8%、7.4%和5.9%;不同批次重复测定15次,其批间CV分别为10.1%、9.6%和12.4%。重组抗原对血清中相应抗体的阻断率为92.2%。通过ROC曲线确定cut off值吸光度(A)为0.209。检测侵袭性念珠菌病(invasive candidiasis,IC)的敏感性和特异性分别为81.6%(93/114)和94.4%(356/377),敏感性高于检测抗Eno抗体的间接ELISA法(81.6%vs 76.1%)。结论建立了双抗原夹心ELISA法检测抗念珠菌Eno特异性抗体,可提高IC的诊断率,具有临床应用价值。