Comparative study of three commerical preparations for the detection of Australia antigen]

2,944 sera from blood donors (420 of them being new donors) were tested in four techniques: Counterelectrophoresis (CEP) and three commercial tests: Ausria II, Auscell and Hepanosticon. Over 10 HBs Ag detected by RIA, 8 were evidenced by the Auscell test and 6 by the Hepanosticon Test. False positive results (approximately 3%) represent a disadvantage to the reverse hemagglutination method; this rate increased considerably in a group of 386 patients sera also tested. The authors conclude that the results obtained with the reverse hemagglutination technique are nearing those of RIA.     

HBs antigen in the blood donors of Calvados. Epidemiologic study and surveillance of the patients

175 Chronic HBs Ag carriers have been discovered in the blood donors of the Calvados blood transfusion center from 1971 to 1979. 72 of them (41%) gave their consent for a clinical and biological study at the end of 1979, after receiving a convocation letter. This work had two aims: - to study the epidemiological factors in this population. - to evaluate the clinical and biological consequences of persistent antigenemia. 1. Epidemiological Study. Most results agree with the literature (higher prevalence in male, age, stay in endemic countries) but some results disagree for several reasons: our donors are all volunteers, HBs Ag prevalence is low in our region, most of the patients are caucasian and with life conditions and habits which may explain some particularities in contagion. Furthermore, the relative number of blood donors found every year as chronic HBs Ag carriers, does not increase in our country. 2. The Clinical and Biological follow-up of 62 HBs Ag carriers (alcoholics excluded) was carried out for 4,3 years on average. No patients developed clinical and biological features of chronic liver disease. After a mean term follow-up, we conclude that the asymptomatic HBs Ag carriers state seems not to be of bad prognostic. Since long term complications cannot be excluded, the follow-up of these patients must be maintained.     

Hepatitis B virus markers, beta 2 microglobulin and anti HTLV in a population of blood donors from a prison environment

212 male prisoners were collected at the prison in March 1983. Anti-HBc and HBs Ag were detected by a combined test (AUSRIA-CORE, Abbott Laboratories). 67 sera (31,5%) were anti-HBc positive, 7 of them HBs Ag positive. Screening for anti-HTLV (anti-p24) was negative for all the donors. Beta 2 microglobulin levels were determined on 115 sera (B2-micro RIA 100, Pharmacia Laboratories). 8 had levels above 2,6 mg/l (greater than 2 SD). These 8 sera were anti-HBc positive and one of them HBs Ag positive 3 HBs Ag positive donors had non elevated Beta 2 microglobulin levels. This survey confirms that prisoners as blood donors should be regarded as carrying a high risk of transmission of HBV and probably other infectious agents with similar epidemiology. The signification of elevated Beta 2 microglobulin levels deserves further investigations since this determination could be of value as an additive test to increase the safety of blood products.     

酶联免疫法和胶体金法在胃镜检查前检测乙肝表面抗原的结果观察

目的:比较酶联免疫法和胶体金法在胃镜检查前检测乙肝表面抗原的结果,以探讨酶联免疫法和胶体金法在检验与病理科乙肝表面抗原检测中的应用价值.方法:选择2017年1月～2019年12月我院进行胃镜检查的100例上消化道疾病患者,均在胃镜检查前检测乙肝表面抗原,对照组使用胶体金法进行检测,观察组使用酶联免疫法进行检测.比较酶联...     

Detection of HBs antigen with latex particles coated with human antibody prepared by affinity chromatography on concanavalin A-sepharose.

Human HBs antibody was isolated by affinity chromatography on HBs antigen absorbed to concanavalin A linked to Sepharose 4B. When a human anti-HBs immunoglobulin preparation obtained by Cohn's cold ethanol fractionation method was used as a starting material, the antibody was concentrated about 10 times in terms of the passive hemagglutination titer with a recovery rate higher than 50%. Latex particles coated with human anti-HBs antibody thus prepared were proved to be useful in detecting HBs antigen in human blood samples. In its sensitivity and in rapidity of its performance, the antibody-coated latex agglutination test seems to be superior to conventional immunodiffusion techniques.     

Evaluation of Passive Hemagglutination, Solid-Phase Radioimmunoassay, and Immunoelectroosmophoresis for the Detection of Hepatitis B Antigen

Sensitivity and specificity of passive hemagglutination (RCA), solid phase radioimmunoassay (RIA), and immunoelectroosmophoresis (IEOP) were compared under experimental and clinical conditions. In dilution experiments with sera containing hepatitis B antigen (HB Ag) of known subtypes, the sensitivity for an ad subtype serum was RIA (1), RCA (1/2), IEOP (1/256) and for an ay subtype serum RCA (1), RIA (1/8), IEOP (1/128). An evaluation of the National Institutes of Health, Division of Biologics Standards test panel number 2 demonstrated HB Ag in 34 of 60 samples by RIA, in 33 by RCA, and in 25 by IEOP. HB Ag was detected in 57.5% of 200 outpatients with a tentative diagnosis of hepatitis by RIA, in 54% by RCA, and in 42.5% by IEOP. In 1,661 volunteer blood donors, 13 (0.78%) were "positive" for HB Ag by RIA, 11 (0.66%) by RCA, and 3 (0.18%) by IEOP. However, absorption experiments indicated that at least six of the above RIA positive and five of the RCA positive sera exhibited nonspecific positive reactions.     

Comparative biophysical studies of hepatitis B antigen, subtypes adw and ayw.

Comparative biophysical and biochemical analyses were performed on purified preparations of hepatitis B antigen (HBs Ag) subtypes adw and ayw, including isoelectric pH evaluations, analysis of the different morphological forms, molecular weight determinations, and analysis of the polypeptides by polyacrylamide gel electrophoresis, Both HBs Ag-positive plasma and purified HBs Ag were analyzed by electrofocusing in a sucrose ampholyte gradient. Four distinct populations of HBs Ag with a pH range of 4.5 plus or minus 0.1 to 5.4 plus or minus 0.1 for unfractionated plasma samples and 3.9 plus or minus 0.05 to 4.9 plus or minus 0.05 for purified samples were detected in both adw and ayw preparations. Electron microscopic studies of each population of purified HBs Ag revealed 19- to 27-nm spheres in each fraction. Purified material labeled with 125I by the chloramine-T method behaved as one major population with an isoelectric pH value of 3.9 plus or minus 0.1. Purified adw preparations revealed a major population with a molecular weight of 3.7 times 10-6 and a second one of 4.6 times 10-6. Purified preparations of ayw contained one population with a molecular weight of 4.6 times 10-6. Polyacrylamide gel electrophoretic analysis of purified HBs Ag revealed nine polypeptides for ayw and seven for adw particles. These studies indicate that purified preparations of HBs Ag are heterogeneous and that distinct differences can be detected between the two subtypes.     

Subclass distribution of antigen-specific IgA antibodies in normal donors and individuals with homozygous C alpha 1 or C alpha 2 gene deletions

To analyze the subclass restriction of Ag-specific IgA, sera and saliva from healthy blood donors and from IgA class or subclass deficient individuals were studied. The latter included donors with or without C alpha 1 or C alpha 2 gene deletions. Monoclonal human IgA1 and a genetically engineered IgA2 antibody, normal human serum and colostrum IgA were used as standards to estimate serum and saliva levels of Ag-specific antibodies. In normal individuals, there was a strong IgA1 preference of naturally acquired antibodies in serum against both polysaccharide Ag (PPS 6A, PPS 23, pneumococcal C-polysaccharide, and LPS from Escherichia coli) and protein Ag (Staphylococcus aureus alpha-toxin and HSV). Specific IgA2 in serum against the tested Ag were frequently not measurable. In contrast, most of the individuals with homozygous C alpha 1 gene deletions displayed substantial amounts of specific IgA2 against protein as well as polysaccharide Ag. The median levels of specific IgA in serum against protein Ag were approximately one-third as compared to normal individuals and one-fifth, or less, against polysaccharide Ag. Normal serum levels of IgA against the tested Ag, restricted to the IgA1 subclass, were noted in two individuals with IgA2 deficiency, one of whom carried a homozygous C alpha 2 gene deletion. Median values of specific IgA, against the tested Ag S. aureus alpha-toxin, HSV, and pneumococcal C-poly-saccharide, from normal healthy donors were approximately four to eight times higher in serum as compared to saliva. Individuals with homozygous C alpha 1 gene deletions displayed increased levels of the various specific IgA2 antibodies in saliva. In conclusion, the individuals with homozygous C alpha 1 gene deletions displayed decreased median levels of specific IgA antibodies in serum despite normal levels of total IgA. Normal levels of both specific IgA and total IgA in saliva were found.     

A microtiter solid-phase radioimmunoassay for hepatitis A antigen and antibody.

A microtiter solid phase radioimmunoassy for hepatitis A antigen (HA Ag) and antibody (anti-HA) was developed. The test was more sensitive than immune adherence hemagglutination for detecting HA Ag and almost as sensitive for detecting anti-HA. The specificity and sensitivity of reagents were examined and optimum conditions for the test were determined. Radioimmunoassay, immune adherence hemagglutination, and immune electron microscopy were compared for detecting anti-HA. A serologic response to HA Ag was detected in paired sera from patients with type A hepatitis but not from patients with type B or non-A, non-B hepatitis by all three techniques.     

Determination of antibody to hepatitis B core antigen by means of immune adherence hemagglutination.

A simple and rapid method utilizing immune adherence hemagglutination has been developed for the detection of antibodies to hepatitis B core antigen (anti-HBc). Hepatitis B core antigen (HBcAG) was prepared from Dane particles that had been isolated from plasma of asymptomatic antigen carriers. The method was specific and about 10 times more sensitive than the conventional complement-fixation method. A total of 215 serum samples obtained from healthy blood donors were surveyed for HBsAG and anti-HEc, as well as for hepatitis B surface antigen (HBsAg) and antibody to HBsAG (anti-HBs). Anti-HBc was found in 36 serum samples, at a prevalence rate higher than that of anti-HBs (31/215)...     

Screening for Chagas disease by immunoenzymology: comparison of ELISA with immunofluorescence and indirect hemagglutination in 976 blood donors

The efficiency of an immunoenzymatic technique (ELISA) for the systematic research of Chagas' disease in blood donors was compared with one of 2 well-known methods, indirect haemagglutination (IHA) and indirect fluoro immuno assay (IFA). For the ELISA technique two different antigenic extracts from epimastigote culture forms of T. cruzi, were used for sensitizing the polystyrene plates: a crude extract (Ag R) and a delipidized one (Ag B). Firstly the authors tested these 3 techniques in 5 control groups: sera from Chagas' disease, negative control sera, sera from visceral leishmaniasis, african trypanosomiasis and finally monoclonal gammapathies, the high levels of blood proteins being a possible cause of false positives. Secondly the screening of Chagas' disease was performed in the same way in 976 blood donors from Recife, Brazil. In the case of the Ag-R extract used in the ELISA technique a high cross-reactivity was found with visceral leishmaniasis sera, along a risk of false positives with gammapathic ones. The sensitivity of this technique was found to be high (3,3 +/- 1 p. cent of positive blood donors) and a very good correlation was found with the reference techniques, IFA and IHA, the sensitivity of which is lower (2,3 +/- 1 and 1,7 +/- p. cent). The use of a delipidized antigenic extract (Ag B) for the ELISA technique is not suitable, in spite of an apparent higher specificity: indeed, the positives rate is high (11,5 +/- 0,2 p. cent), but the correlation is very weak or non existent in the case of IHA or IFA. In conclusion, the ELISA technique using a crude extract of T. cruzi appears to be a very convenient method for screening blood donors with Chagas' disease, the lack of specificity due to leishmaniasis or monoclonal blood proteins not posing any real problem to blood banking.     

The use of the latex agglutination reaction for the diagnosis of a Brucella infection

The authors have developed the optimum conditions for the preparation of antigenic diagnosticum based on latex manufactured in the USSR. To sensitize latex with the diameter of microspheres equal to 0.83 microns, Brucella polysaccharide was used in a dose of 100 micrograms/ml. As stabilizer, polyvinylpyrrolidone at a concentration of 0.1% was used. The specificity and sensitivity of the diagnosticum were studied in analysis of serum samples taken from 102 healthy donors and patients with infectious diseases of nonbrucellar etiology and from 120 patients with different forms of brucellosis. The specificity of the diagnosticum was found to be 94.1% and its sensitivity, 77.5%. Comparative study of the latex agglutination test with other serological tests showed that the former test is highly effective both in acute and chronic forms of the disease. A high degree of correlation between the agglutination test, Coombs' test, the passive hemagglutination test and the latex agglutination test was established (r = 0.83, 0.72 and 0.62, respectively).     

Comparison of the Direct Agglutination and Indirect Hemagglutination Tests in the Determination of Blood Serum Titers to Escherichia coli Organisms

A comparison of the direct agglutination test and the indirect hemagglutination test for the detection of blood serum antibodies to Escherichia coli organisms indicated that these serological tests were comparable. In some instances the indirect hemagglutination test provided higher endpoint readings. Preparation of the antigens for the indirect hemagglutination test was more time consuming than for the direct agglutination test. Crude extract and purified polysaccharides were comparable as red blood cell sensitizing agents.     

Diagnostic value of a dot immunobinding assay for human pulmonary hydatidosis

The diagnosis of human hydatidosis is primarily made using radiological and serological methods. Radiological methods are generally of low specificity and serological methods lack sensitivity, especially for pulmonary disease. In this study the capabilities of a new rapid test, the hydatid antigen dot immunobinding assay (HADIA), which was developed for the diagnosis of pulmonary hydatidosis, were studied and compared with another immunodiagnostic method, indirect hemagglutination (IHA). The study subjects included 18 patients, 9 women, 9 men; range 7 to 63 years; mean 30 years, with surgically proven pulmonary hydatidosis, a control group comprised of 14 patients; viral respiratory infections (1), cirrhosis (2), connective tissue disease (2), taeniasis (3), and 6 healthy donors. We found that the HA-DIA test had a sensitivity of 67% and specificity of 100%, and that the IHA test had a sensitivity of 50% and specificity of 100%. We conclude that HA-DIA is a simple, rapid, low cost assay that does not require instrumentation and has a higher sensitivity than IHA for the diagnosis of pulmonary hydatidosis.     

Family diffusion of HBs antigen]

Systematic investigation for HBs antigen and for HBs antibody in donors carrying HBs antigen evidenced a familial contamination more important in children and first cousins than in husband and wife which confirm various previous studies. Moreover, daughters and sisters of antigen carriers show an abnormaly high antigen frequency and especially an abnormally low antibody frequency.     

Evaluation of a Red Cell Agglutination Test for Detection of Australia Antigen (HB Ag)

An investigational red cell agglutination (RCA) test was evaluated for sensitivity in detecting and titering hepatitis B antigen (HB Ag) in comparison with two counterelectrophoresis (CEP) systems and a solid-phase radioimmunoassay (RIA). The RCA procedure was found to be significantly more sensitive than the CEP methods and compares favorably in sensitivity with the solid-phase RIA, detecting even lower concentrations of the HB Ag. Since the RCA test can be completed in 2 to 3 h and requires relatively inexpensive equipment, it offers a highly sensitive and rapid procedure suitable for use in blood banks to screen donors or detect low levels of antigen in serum of patients.     

Use of the indirect hemagglutination test for the study of ornithosis. Report 2. Preparation and approbation of the dry ornithosis erythrocyte diagnostic agent

An original preparation--dry ornithosis erythrocytic diagnostic agent for the indirect hemagglutination test was prepared on the basis of formalinized tannin-treated sheep red blood cells and group-specific phospholipid antigen of the causative agent of ornithosis. This diagnostic agent retained its specific activity for 18 months (observation period). The use of this preparation considerably facilitated the method of performance of this test, this offering a possibility of its wide application in practice. A sufficiently high sensitivity and specificity of the indirect hemagglutination test with the suggested diagnostic agent, in comparison with the complement fixation test was demonstrated.     

Specificity of the serological diagnosis of dysentery using erythrocytic reagents

The serological specificity of the diagnosis of dysentery, made by different methods with the use of antigenic and antibody erythrocyte diagnostic agents under the conditions of the circulation of different Shigella species and subspecies in a given locality, has been compared. The method for the determination of the diagnostic titer of the total serum antibody activity has proved to be the least specific. The methods for the detection of Shigella antigens, especially over time, in patients' excretions and for the determination of serum antibody activity show complete specificity. The combination of specificity and sensitivity makes the detection of Shigella antigens in feces by means of the passive hemagglutination test and the antibody neutralization test the method of choice for the diagnosis of dysentery.     

Secretory expression of E2 main antigen domain of CSFV C strain and the establishment of indirect ELISA assay

The sequence encoding an E2 main antigen glycoprotein of the C strain of classical swine fever virus (CSFV) was highly expressed in the host cell E. coli BL21-CodonPlus (DE3)-RIL using the pGEX-4T-1 expression vector and the soluble recombinant product was purified with Glutathione Sepharose TM<'4B> by centrifugation. The soluble recombinant protein showed good immune reactions and was confirmed by Western blot using anti-CSFV-specific antibodies. Then an indirect ELISA with the purified E2 protein as the coating antigen was established to detect antibody against CSFV. The result revealed that the optimal concentration of coated antigen was 0.6 μg/well and the optimal dilution of serum was 1:80. The positive cut-off value of this ELISA assay was OD<,tested serum>/OD<,negative serum>≥2.1- The E2-ELISA method was evaluated by comparison with the indirect hemagglutination test (IHAT). When a total of 100 field serum samples were tested the sensitivity and specificity were 90.3% and 94.7% respectively. Specificity analysis showed that there were no cross-reactions between BVD serum and the purified E2 protein in the E2-ELISA.     

研究报告：蚓激酶同工酶降解乙型肝炎抗原并保护肝功能

目的蚓激酶同工酶(LKIs)作为肠溶胶囊的有效成分,用于治疗血栓性疾病已有30多年历史。近年来,LKIs在其他危重疾病中的研究时有报道。本文关注LKIs在乙型肝炎方面的作用。方法乙型肝炎表面抗原(HBs Ag)、核心抗原(HBcAg)和e抗原(HBeAg)分别与不同浓度LKIs孵育,观察这些蛋白质的降解和估计肽链的切割位点。Hep G2.2.15细胞与LKIs孵育,采用酶联免疫吸附测定(ELISA)和蛋白质印迹(Western blotting)检测细胞分泌的HBsAg和HbeAg。LKIs灌胃Balb/c小鼠30天,采用ELISA和Western blotting检测其血清HBsAg和HBeAg,免疫组化染色检测肝组织中的HBcAg。采用苏木精-伊红染色分析乙肝病毒转基因小鼠肝组织的损害,并通过ELISA定量分析血清谷草转氨酶(GOT)和谷丙转氨酶(GPT)。腹腔注射后,取大鼠血清和肝组织,测定其中的LKIs含量,从而观察LKIs的吸收。采用LKIs给龙岩麻鸭灌胃30天,通过PCR检测其血清HBV DNA。结果蚓激酶肠溶胶囊的有效成分是含有6种LKIs的复方蛋白酶药物,可以降解HBV...