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

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

Equine infectious anaemia virus is related by genome sequence homology to human immunodeficiency virus, caprine arthritis-encephalitis virus and visna virus. Failure of the host to mount a strong neutralizing response detectable in vitro or to eliminate persistent infection in vivo characterizes lentivirus infections in the natural host. In this study the specificities and neutralizing activity of antibodies induced during experimental infection with equine infectious anaemia virus were investigated using antiviral ELISA, radioimmunoprecipitation and neutralization assays. ELISA antibody titres of 10(5) to 10(6) were demonstrated in samples collected 30 and 60 days after infection. Immunoprecipitation titrations demonstrated that antibody titres to the glycoproteins gp90 and gp45 were 10 to 100 times higher than titres to the internal structural protein, p24. Low levels of neutralizing antibody appeared at 23 to 46 days post-infection. The presence of low levels of neutralizing activity in the presence of high levels of anti-glycoprotein activity suggests that the major immunogenic sites on the viral surface are not sensitive to neutralization.
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PMID:Antiviral, anti-glycoprotein and neutralizing antibodies in foals with equine infectious anaemia virus. 335 80

One hundred and eighty-four serum specimens were assayed for antibodies to the human immunodeficiency virus. All specimens were screened with a commercial enzyme immunoassay and confirmed by two indirect immunofluorescence assays. Sera were also assayed by Western blot. Results from sera of 48 healthy heterosexual volunteers were all negative by EIA, IFA, and Western blot. Sera from 50 healthy homosexual men negative by EIA were also negative by IFA and Western blot. Sixty-two patients with persistent generalized lymphadenopathy or newly diagnosed AIDS all were positive by EIA, IFA, and Western blot. Of 24 sera from patients with autoantibodies, with no evidence of AIDS-related diseases, five appeared to be false-positive by EIA, since they were nonreactive by IFA and Western blot. In addition, three other samples contained both autoantibodies and human immunodeficiency virus antibodies. False-positive results were observed in both the EIA and IFA with monoclonal antibodies directed toward the MHC class II antigens DQ and DR. The reactivity of these antibodies could not be distinguished from positive patients' sera, in either EIA or IFA. We conclude that in general indirect immunofluorescence performed well as a confirmatory test after screening by enzyme immunoassay for human immunodeficiency virus antibodies.
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PMID:Evaluation of the indirect immunofluorescence assay as a confirmatory test for detecting antibodies to the human immunodeficiency virus. 353 56

To detect human immunodeficiency virus (HIV) antibodies in a simple enzyme-linked immunoassay (CBre3-EIA), we used an Escherichia coli-expressed polypeptide antigen, representing the carboxy-terminal third of the external membrane glycoprotein gene fused with the amino-terminal half of the transmembrane glycoprotein gene. Over a 3-month period, 2707 consecutive serum samples referred for confirmatory testing for human T-lymphotrophic virus type III (HTLV-III) antibodies were evaluated by both Western blot and CBre3-EIA. On a single determination for each sample, the CBre3-EIA was found to have an estimated sensitivity (99.9%) and specificity (99.1%) similar or superior to the more cumbersome Western blot method. This study shows that all HIV-seropositive subjects have antibodies to the virus envelope protein; no other virus antigens are required for construction of highly sensitive immunoassays.
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PMID:Diagnosis of human immunodeficiency virus infection by immunoassay using a molecularly cloned and expressed virus envelope polypeptide. Comparison to Western blot on 2707 consecutive serum samples. 355 11

Plasma levels of complement (C) fragments iC3b, C4d, and Bb from human T cell leukemia virus (HTLV)-positive subjects with HTLV-I-associated myelopathy (HAM)/tropical spastic paraparesis (TSP) were analyzed by EIA. Both iC3b and C4d levels were significantly elevated in persons with HAM/TSP. These levels were similar to those in patients with human immunodeficiency virus (HIV) infection or rheumatoid arthritis (RA), who are known to have increased C fragments. Bb levels in persons with HAM/TSP wer unaffected, suggesting that C activation occurred only via the classical pathway. This differed from findings in HIV-infected or RA patients, who had elevated levels of Bb. The results showed an increase in C activation in persons with HAM/TSP and activation via the classical pathway, likely mediated by virus or immune complexes. It is possible that the C activation observed in these subjects contributed to the inflammatory pathogenesis of HAM/TSP.
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PMID:Elevated levels of iC3b and C4d, but not Bb, complement fragments from plasma of persons infected with human T cell leukemia virus (HTLV) with HTLV-I-associated myelopathy/tropical spastic paraparesis. 756 Nov 87

Hepatitis C virus (HCV) is a major cause of transfusion-induced chronic liver disease in hemophiliacs, with 70% to 90% being anti-HCV positive. Seroreversion or loss of antibody response to HCV has been observed in a small proportion of human immunodeficiency virus-positive [HIV(+)] anti-HCV(+) hemophilic men. Despite the seroreversion to an anti-HCV-negative state, such patients continue to show serum alanine aminotransferase (ALT) elevations and biopsy evidence of cirrhosis and/or chronic active hepatitis. To determine the cause for the loss of anti-HCV antibody, we compared first- and second-generation anti-HCV enzyme immunosorbent assay (EIA 1.0 and 2.0), second-generation recombinant immunoblot (RIBA 2.0), and HCV-RNA amplification using polymerase chain reaction (PCR) in 19 "seroreverters" before and after seroreversion. There was no difference between 19 seroreverters and 59 persistently anti-HCV-positive hemophiliacs in mean ALT (1.1 +/- 0.1 XUL v 2.0 +/- 0.2 XUL; chi 2 = 1.80, P > .05), in mean CD4 (188 +/- 36/microL v 232 +/- 28/microL; t = 0.965, P > .05), or in the rate of progression to acquired immunodeficiency syndrome (13 of 19 [68.4%] v 30 of 59 [50.9%]; chi 2 = .987, P > .05, respectively). Before seroreversion, all 19 seroreverters (100%) were positive for EIA 1.0 and 2.0 and PCR, and all but 2 of 19 (89.5%) were RIBA 2.0 positive, whereas, after seroreversion, none were positive for EIA 1.0, 15 of 19 (78.9%) were positive for EIA 2.0, 8 of 18 (44.4%) were positive for RIBA 2.0, and 18 of 19 (94.7%) were positive for PCR. There was a lower CD4 lymphocyte number after seroreversion in those who were RIBA 2.0 negative as compared with those who were RIBA 2.0 positive (32 +/- 10/microL v 171 +/- 52/microL; t = 2.638, P > .05). These results indicate that HIV(+) anti-HCV(+) hemophilic men who undergo "HCV seroreversion" are truly infectious and anti-HCV positive by second-generation tests. Anti-HCV detection in immunosuppressed hosts is significantly improved by second-generation EIA and RIBA assays.
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PMID:The presence of hepatitis C virus (HCV) antibody in human immunodeficiency virus-positive hemophilic men undergoing HCV "seroreversion". 768 87

Seroprevalence of human T lymphotropic virus (HTLV) and human immunodeficiency virus type 1 (HIV-1) was determined among 7841 intravenous drug users (IVDUs) from drug treatment centers in Baltimore, Chicago, Los Angeles, New Jersey (Asbury Park and Trenton), New York City (Brooklyn and Harlem), Philadelphia, and San Antonio, Texas; 20.9% had evidence of HTLV infection, as determined using a p21e EIA for screening and p21e blot for confirmation. With a type-specific EIA and blot used in combination, HTLV-II was identified in 97.6% of HTLV-positive IVDUs whose sera could be subtyped. HIV-1 seroprevalence was 13.2%. HTLV-II without HIV-1 was most common in Los Angeles and San Antonio. HIV-1 without HTLV-II was most common in New York, New Jersey, and Baltimore. Dual infection was most common in New York and New Jersey. Logistic regression analysis revealed that seroprevalence of HTLV-II was significantly greater with HIV-1 infection and increasing age and among women, blacks, and Mexican-Americans. In conclusion, it appears that among US IVDUs, nearly all HTLV infection is attributable to HTLV-II, and HTLV-II infection is associated with HIV-1 and sociodemographic background.
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PMID:Seroprevalence of human T cell lymphotropic virus type II infection, with or without human immunodeficiency virus type 1 coinfection, among US intravenous drug users. 779 46

Two EIAs (Medgenix and Quantikine) and a bioassay were used to measure tumor necrosis factor-alpha (TNF alpha) in serum samples from 73 human immunodeficiency virus type 1 (HIV-1)-seropositive patients and in samples from 2 control groups. All clinical groups of HIV-1-infected patients, regardless of concurrent illness, had significantly elevated levels of both types of soluble TNF receptors (sTNFRs) and immunoreactive TNF alpha (Medgenix EIA), with the highest concentrations among the AIDS patients. These TNF parameters were significantly correlated with reduced CD4+ lymphocyte counts. Only a few HIV-1-infected patients had detectable TNF alpha levels measured by the Quantikine EIA. TNF alpha bioactivity was significantly raised only in the AIDS group. Serially measured sTNFRs, expressed as sTNFR slopes, were significantly associated with survival in the patient group. The raised levels of immunoreactive TNF alpha and sTNFRs strongly indicate activation of the TNF alpha system during HIV-1 infection. Levels increase with disease progression and degree of immunodeficiency; thus, serially measured sTNFRs may give useful prognostic information in HIV-1 infection.
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PMID:Serum levels of tumor necrosis factor-alpha (TNF alpha) and soluble TNF receptors in human immunodeficiency virus type 1 infection--correlations to clinical, immunologic, and virologic parameters. 790 93


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