Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To evaluate the performance of a serological test for human immunodeficiency virus type 1 (HIV-1) infections based on the use of a recombinant envelope gene-derived protein as the antigen, we caused expression of a 1.4-kilobase fragment of HIV.DNA that codes for the complete gp41 transmembrane protein in an Escherichia coli expression vector and used Western blots (WB; immunoblots) prepared with recombinant material (pEX-41) to detect antibodies to HIV-1. This test detected all 339 sera which were positive by a combination of conventional serodiagnostic assays and produced no false-positive results with 311 negative samples. Also no false-positive results were obtained with 20 sera from systemic lupus erythematosus patients which had high titers of cross-reactive autoantibodies. In six cases, the pEX-41 WB proved to be more sensitive than individual assays applied on their own, and in five cases it was even more sensitive than a combination of conventional assays. We tested 221 sera in both our pEX-41 WB and a commercially available recombinant enzyme immunoassay (EIA [Abbott]). The results were identical in 188 cases. A total of 27 sera containing antibodies to gp41 as demonstrated in the pEX-41 WB, as well as the Abbott recombinant EIA, had no antibodies to the recombinant core antigen as measured in the Abbott EIA. However, 25 of these sera did stain the 24-kilodalton band on a WB with purified virus. Six sera that were positive in all of the conventional confirmatory assays and reacted strongly with the pEX-41 WB did not recognize the surface antigen used in the Abbott recombinant EIA. We conclude that the use of WB prepared with recombinant-derived p41 offers a very sensitive and specific method to detect antibodies to HIV.
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PMID:Comparison of Western blot (immunoblot) based on recombinant-derived p41 with conventional tests for serodiagnosis of human immunodeficiency virus infections. 327 88

51 human sera containing antibodies to human immunodeficiency virus 1 (= HIV-1) were examined for HIV-1-antigen by three different enzyme immunoassay procedures (= EIA) of Abbott, Organon and Dupont. Sensibilities, handling as well as the correlation with the clinical stages of HIV-infection were compared. The EIA's diagnosed in accordance 6 sera which contained HIV-1-antigen and 42 sera to be HIV-1-antigen negative. 3 sera showed differences: according to the EIA of Organon none of these sera contained HIV-1-antigen, the EIA of Abbott (but not of Dupont) analysed HIV-1-antigen in one of these sera, in the other two sera only the EIA of Dupont showed HIV-1-Antigen. It is concluded that the differences in these 3 serum samples may originate not only in the different types of EIA used (indirect/direct procedure) but also in the different capture antibodies provided (antibodies against p-24 antigen or polyvalent antibodies).
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PMID:[Detection of HIV-1 antigen--determination using 3 different test systems]. 328 30

Two commercial enzyme-linked immunosorbent assays (EIAs) for human immunodeficiency virus (HIV) antigens were evaluated for sensitivity and reproducibility by use of supernatant fluid from cell cultures of peripheral mononuclear cells of 18 patients with acquired immunodeficiency syndrome (AIDS) and 12 asymptomatic HIV antibody-positive patients. Both commercial assays detected HIV antigen in all cultures by day 21; however, the Abbott HIV antigen EIA (Abbott Laboratories, North Chicago, IL) detected HIV antigen three to seven days earlier in 15 of 48 cultures (31%), on the same day in 32 cultures (67%), and three days later in 1 culture (2%) when compared with the DuPont HIV antigen EIA (DuPont Laboratories, Wilmington, DE). In serial twofold dilution experiments, the Abbott HIV Ag EIA was found to have at least a twofold to eightfold increased sensitivity over the DuPont assay. Repeat testing of 15 initially positive supernatant fluids by both assays revealed that 13 of 15 and 12 of 15 were consistently positive by the Abbott and DuPont assays, respectively. The authors conclude that the Abbott EIA demonstrated better performance in this study than the DuPont EIA for detection of HIV in cell culture because of its shorter time-to-positivity and greater sensitivity.
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PMID:Evaluation of two commercial tests for human immunodeficiency virus antigens in culture supernatant fluid. 328 60

The second-generation enzyme immunoassays (EIAs) for antibodies against human immunodeficiency virus (HIV) from three manufacturers (Abbott, Organon, Wellcome) and three anti-HIV confirmatory tests, i.e. Western Blot (WB, Biotech, Dupont), radioimmunoprecipitation assay (RIPA, CLB) and a competitive immunoassay (CIA, Abbott) were evaluated on a panel of 6,488 serum samples, which had previously been used for the comparison of seven first-generation EIAs. For the present study the panel was expanded with sequential serum samples from 12 individuals followed at 1- to 3-month intervals during seroconversion for anti-HIV. The second-generation EIAs and confirmatory tests were significantly more sensitive than the first-generation EIAs as was demonstrated by detection of 10- to 100-fold higher endpoint titers in anti-HIV-positive sera as well as by earlier detection of anti-HIV in 7-11 of the 12 subjects, who seroconverted. In all sera obtained during early HIV infection anti-gp 160/120env antibodies (WB, CIA) were found in addition to anti-p24 (WB, RIPA) and in serial twofold dilutions of these 'seroconversion samples' the new Abbott EIA and RIPA were significantly more sensitive than WB (p less than 0.05), whereas CIA and the new Organon EIA were significantly less sensitive than WB (p less than 0.05). The new Wellcome EIA was not statistically less sensitive than WB. The CIA was as sensitive as WB for antibodies to envelope proteins (gp41, gp160, gp120), but considerably less sensitive for core (p24) antibodies, as was shown in sera obtained during early as well as later clinical stages of HIV infection.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Evaluation of three second-generation and three confirmatory assays for antibodies to human immunodeficiency virus. 328 66

A total of 152 sera from African subjects were tested for presence of antibody to human immunodeficiency virus using four enzyme immunoassays (EIA) marketed by Abbott Diagnostics, Organon Teknika, Wellcome and Diagnostics Pasteur respectively, an indirect immunofluorescence assay (IFA) and an immunoblot assay (IBA) as reference test. The sensitivity (95% confidence limits, CL) of the EIAs and the IFA ranged between 80.9% and 99.1%. The specificity of the Abbott EIA was lower (95% CL: 38.1-72%) than that of the other assays (95% CL: 83.5-100%). The use of an IFA or the Wellcome competitive EIA as confirmatory test on initially EIA positive sera yielded a specificity of 85.5-100% (95% CL) compared with the IBA. The costs of screening by an EIA, followed by confirmatory testing of reactive sera with IFA or the Wellcome EIA and IBA on discrepant test results was similar for all combinations with the exception of initial screening with the Abbott EIA which was more expensive. Using a limited number of sera from African subjects no one test system yielded a significantly superior degree of specificity or sensitivity.
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PMID:Comparison of enzyme immunoassays and an immunofluorescence test for detection of antibody to human immunodeficiency virus in African sera. 329 80

Screening for human immunodeficiency virus (HIV) (LAV/HTLV-III) antibodies in 3 blood donor populations from India (n = 1,000), Nigeria (n = 500) and Thailand (n = 650; sampling in 1982) with a sensitive enzyme immunoassay (EIA; Abbott) yielded seropositivity rates of 0.5, 2.2 and 1.7%, respectively. Two EIAs with control antigens prepared from uninfected cell cultures ('ELAVIA', VIRGO'), a recombinant Escherichia coli DNA EIA ('ENV/CORE'), Western blot, an immunofluorescence assay and a radio-immunoprecipitation assay confirmed none of the EIA-reactive specimens as truly positive. The lack of specificity of the screening test was also attributable to monochromatic evaluation of the test trays at 492 nm only, and to reactivities against determinants of H9 cells used to grow HIV (HLA antibodies).
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PMID:Human immunodeficiency virus antibody screening in blood donors from India, Nigeria and Thailand. 330 27

A current concept of the serological response to human immunodeficiency virus (HIV) infection in humans is that antibodies to core antigens (p55, p24, and p15) are detectable earlier during initial stages of antibody production than antibodies against envelope antigens (gp160, gp120, and gp41). Comparative studies of Western blot (immunoblot), radioimmunoprecipitation assay (RIPA), and enzyme-linked immunosorbent assay (ELISA) during initial antibody production are limited to case reports and have not resolved the issue. Thirty of the 37 participants who are part of a prospective study had at least one specimen that was negative for anti-gp41 but had one or more other bands on Western blot. Twenty-seven of these 30 specimens were reactive for anti-gp120/160 in the RIPA. Of the same 30 specimens, kits from Bionetics identified 2 (7%), ElectroNucleonics 4 (13%), Abbott 13 (43%), Du Pont 25 (83%), and Genetic Systems 25 (83%). All participants had evidence of serological progression by Western blot, including a gp41 band, on subsequent visits; the ELISA kits of all manufacturers identified these later specimens with greater accuracy. These data show that the RIPA detects anti-envelope antibodies that may be not detectable by Western blot and that the production of anti-envelope antibodies approximately parallels the production of anti-core antibodies. The false-negative results by ELISA would permit transmission of HIV by blood transfusion from donors in early stages of infection. The sensitivity of licensed ELISA kits should be improved to identify antibody as soon as possible after infection.
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PMID:Detection of early antibodies in human immunodeficiency virus infection by enzyme-linked immunosorbent assay, Western blot, and radioimmunoprecipitation. 347 69

Abbott and Wellcome enzyme linked immunosorbent assays (ELISAs) for detection of antibodies to human immunodeficiency virus (HIV) were compared in tests on 932 sera collected predominantly from male homosexuals attending a sexually transmitted disease (STD) clinic in central London. Two hundred and twenty three sera had HIV antibodies detected by both types of assay, with confirmation of the results by further tests carried out at the Virus Reference Laboratory (VRL) in Colindale. There was a 97.3% correlation between the results obtained by the two commercial ELISA assays on the tests carried out on unheated sera. The Abbott ELISA gave significantly more false positive results than the Wellcome test when the manufacturer's instructions for cut off values were followed. There was one false negative Abbott results: it failed to react to repeated Abbott ELISA but was positive by Wellcome and confirmatory assays. Of 283 heat treated sera 14.8% gave falsely reactive results with the Abbott assay whereas there were no differences between heated and unheated sera with the Wellcome assay. VRL or Western blot confirmatory assays, or both, confirmed all the 235 positive results obtained with the Wellcome assay.
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PMID:Clinical evaluation of Abbott and Wellcome enzyme linked immunosorbent assays for detection of serum antibodies to human immunodeficiency virus (HIV). 364 47

We compared an automated microparticle double-antigen sandwich enzyme immunoassay (EIA) for the IMx test system recently developed by Abbott with two established assays (the automated indirect Vidas IgG EIA and the double-antigen sandwich EIA from Murex/Wellcome) devised for the detection of human immunodeficiency virus type 1 (HIV-1) and HIV-2 antibodies. A total of 1,078 consecutive serum samples were tested prospectively with the three assays. In addition, we used retrospectively selected panels of serum samples with discrepant results in two different screening tests and with indeterminate or positive Western immunoblot (WB) results, as well as five commercially available HIV-1 seroconversion panels. The new assay showed excellent discriminatory characteristics for the separation of samples from HIV-1-positive and HIV-1-negative persons according to Centers for Disease Control and Prevention WB criteria. The sensitivities were 98.1, 92.9, and 96.1% for the new test and the two other assays, respectively, and the specificities were 99.7, 97.9, and 98.1%, respectively. With the seroconversion panels this new test was positive several days earlier than the two other assays; i.e., seroconversion was evident at the peak of p24 antigenemia and often several weeks before WB became positive by the most stringent criteria.
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PMID:Detection of human immunodeficiency virus (HIV) type 1 antibodies by new automated microparticle enzyme immunoassay for HIV types 1 and 2. 749 24

Paired serum and oral fluid specimens (n = 287) were collected with the Omni-Sal device and were assayed for the presence of antibodies to human immunodeficiency virus type 1 (HIV-1). Enzyme immunoassays (EIAs)--Abbott 3A11, an Organon Teknika Corporation research-use-only test, and the Murex GACELISA--were used per the manufacturers' inserts or were modified slightly to accommodate the oral fluid specimens. Compared with serum Western blot (immunoblot) results, each EIA had a sensitivity of 100% and the specificities were 89.6% for the Abbott 3A11 EIA, 96.5% for the GACELISA, and 97.8% for the Organon Teknika Corporation EIA. Specificities based on specimens that were repeatedly reactive were 99.3% for all EIAs. A miniaturized Western blot technique used for confirmatory testing of both the serum and oral fluid specimens found 149 of the 287 samples to be HIV-1 antibody positive in both sample types. The Western blot banding patterns observed for the serum and oral fluid specimens were essentially identical. Immunoglobulin G concentrations were determined for all oral fluid specimens and ranged from < 0.5 to > 40.0 micrograms/ml. Immunoglobulin G concentrations did not correlate with the ability of any of the EIAs to detect HIV-1-specific antibody or with the ability of the modified Western blot to detect HIV-1 protein-specific antibodies.
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PMID:Oral fluid as a specimen for detection and confirmation of antibodies to human immunodeficiency virus type 1. 758 12


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