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)

We investigated the performance of a double-antigen sandwich recombinant enzyme immunoassay (EIA; Abbott Laboratories, North Chicago, Ill.) and compared it with that of a synthetic-peptide-based EIA (Biochem Immunosystems, Montreal, Quebec, Canada) for the detection of human immunodeficiency type 1 (HIV-1) and HIV-2 antibodies in 2,321 clinical serum samples. The results of both EIA methods and Western blot (immunoblot) were in agreement for 1,046 HIV-1 and 10 HIV-2 specimens from a panel of known positives. From a prospective panel of 1,085 specimens, 38 proved to be positive by both EIAs and Western blot, 3 were positive by the recombinant EIA only, and 9 were positive by the peptide EIA only, for calculated specificities of 99.71 and 99.04%, respectively. Of 180 specimens from a seroconversion panel collected from 77 patients, the results for 170 were in agreement by all antibody testing methods and 10 were found to be repeat reactive for HIV antibodies by the recombinant EIA only. All 10 were initial specimens of seroconverting patients; 7 were also reactive for HIV p24 antigen. An examination of four of these sera by radioimmunoprecipitation assay showed gp120 and gp160 bands in each. Analysis of the anti-Env antibody class in three of these samples showed that one consisted of immunoglobulin M (IgM) only and two contained both IgG and IgM antibodies. Although both EIA procedures were sensitive and specific in the detection of antibodies to HIV-1 and HIV-2 and both were capable of detecting early antibodies, the recombinant assay was more sensitive for antibody detection during early seroconversion.
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PMID:Performance characteristics of recombinant enzyme immunoassay to detect antibodies to human immunodeficiency virus type 1 (HIV-1) and HIV-2 and to measure early antibody responses in seroconverting patients. 881 30

Equine infectious anemia virus (EIAV), the causative agent of infectious anemia in horses, is a member of the lentiviral family. The virus-encoded proteinase (PR) processes viral polyproteins into functional molecules during replication and it also cleaves viral nucleocapsid protein during infection. The X-ray structure of a complex of the 154G mutant of EIAV PR with the inhibitor HBY-793 was solved at 1.8 A resolution and refined to a crystallographic R-factor of 0.136. The molecule is a dimer in which the monomers are related by a crystallographic twofold axis. Although both the enzyme and the inhibitor are symmetric, the interactions between the central part of the inhibitor and the active site aspartates are asymmetric, and the inhibitor and the two flaps are partially disordered. The overall fold of EIAV PR is very similar to that of other retroviral proteinases. However, a novel feature of the EIAV PR structure is the appearance of the second alpha-helix in the monomer in a position predicted by the structural template for the family of aspartic proteinases. The parts of the EIAV PR with the highest resemblance to human immunodeficiency virus type 1 PR include the substrate-binding sites; thus, the differences in the specificity of both enzymes have to be explained by enzyme-ligand interactions at the periphery of the active site as well.
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PMID:Structure of equine infectious anemia virus proteinase complexed with an inhibitor. 884 37

The aim of this study was to compare the performance of differential polymerase chain reaction (PCR) typing and peptide enzyme-linked immunosorbent assay (V3-EIA) for human immunodeficiency virus type 1 (HIV-1) subtyping in Thailand using heteroduplex mobility assay (HMA) as the reference standard. Paired peripheral blood mononuclear cells (PBMC) and sera were collected from 38 HIV-1 seropositive persons in Thailand. HMA was done by standard methods; differential PCR employs primer pairs that differentially amplify either subtype E or B. V3-EIA used peptides specific for subtypes E or B. Thirty-two cases (84%) were found by HMA to be infected with subtype E: and six with (16%) subtype B. The results obtained with differential PCR were 100% concordant with those of HMA; V3 EIA correctly predicted the subtype in 95% (36 of 38). Six samples that molecularly subtyped as E were repeatedly dual reactive by screening V3-EIA, but these resolved to subtype E using an antigen-limiting EIA. Two samples were serologically nontypeable because of overall low levels of V3 antibody. Using HMA as the standard, differential PCR was shown to subtype HIV-1 reliably from patient PBMC samples. V3-EIA correctly predicted HIV-1 subtype in most (95%) of our cases. Because of the less rigorous sampling requirements, specimen processing, and logistical and technical requirements of serotyping compared with molecular techniques, it appears to be practical for screening purposes in a field environment. Samples that cannot be definitively subtyped serologically should undergo differential PCR and antigen-limiting V3 EIA. These approaches to HIV-1 subtyping should be used in complementary fashion in Thailand, where subtypes B and E are currently known to cocirculate.
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PMID:Correlation of genetic and serologic approaches to HIV-1 subtyping in Thailand. 894 79

A new automated microparticle enzyme immunoassay (MEIA) for the AxSYM instrument developed recently by Abbott Laboratories was compared with two established assays, i.e. HIV-1/HIV-2 3rd Gen. Plus EIA (Abbott, Delkenheim, FRG) and Wellcozyme HIV 1 + 2 (Murex Diagnostics, Dartford, England) devised for the detection of human immunodeficiency virus type 1 (HIV-1) and HIV-2 antibodies. A total of 7293 serum samples were tested by the AxSYM HIV-1/HIV-2. The test panel included seroconversions (n = 22), samples from HIV-1 and HIV-2 positive individuals, hospitalized patients, blood donors, high risk individuals. To challenge further the specificity of the assays, large numbers of EIA repeatedly reactive but Western blot negative samples, potentially cross-reactive sera, Western blot indeterminate specimens and samples from pregnant women were tested. In four seroconversion panels, HIV-1 infection was detected one bleed earlier with the AxSYM HIV-1/HIV-2 than with the Abbott HIV-1/HIV-2 3rd Gen. Plus EIA. Although the AxSYM HIV-1/HIV-2 was tested with a higher number of challenging sera than the alternative assays, the specificity was very high (99.4%). The highest number of false positive results was obtained with serum samples that were repeatedly reactive in EIAs different from those compared in the present study. The automated AxSYM system permits the testing of a large sample number in a rapid turn-around time and by random access urgent tests can be carried out even when an assay is in progress.
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PMID:Detection of human immunodeficiency virus type 1 and type 2 antibodies by a new automated microparticle immunoassay AxSYM HIV-1/HIV-2. 901 84

Early (pre-seroconversion) infection with human immunodeficiency virus type 1 (HIV-1) was identified in 50 of 267 participants in the Multicenter AIDS Cohort Study. These 50 men had a positive EIA result, which detected IgM antibody (n = 35), p24 antigen, or serum HIV RNA (n = 15) at their last "seronegative" visit. At that visit, the mean CD4 lymphocyte number (890/mm3 vs. 1038/mm3) was significantly lower than in men who subsequently seroconverted but had no evidence of early infection. The decline in CD4 cells was slower and the duration of AIDS-free time longer in the 19 men who were symptomatic in comparison to the 31 asymptomatic men with early infection, but differences were not significant.
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PMID:Detection of infection with human immunodeficiency virus type 1 before seroconversion: correlation with clinical symptoms and outcome. 908 59

The human immunodeficiency virus type 1 (HIV-1) Western blotting (immunoblotting) band patterns and the sensitivity of an HIV-1 DNA PCR assay were determined by testing the blood of patients with AIDS. Plasma and cell pellets processed from the peripheral blood of 199 patients with absolute CD4 cell counts of less than 200 cells per mm3 were tested by a licensed enzyme immunoassay (EIA; Abbott HIV-1) and Western blot assay (Cambridge-Biotech) for HIV-1 antibody. The Roache HIV-1 AMPLICOR DNA PCR assay was used to test cell pellets from 125 of the 199 patients for HIV-1 gag DNA sequences. All plasma samples from these 199 sequential patients were reactive for HIV-1 antibody by EIA and were positive by Western blot assay using the criteria recommended by the Centers for Disease Control and Prevention. The majority of samples (192 of 199; 96.5%) displayed at least six of nine bands characteristic of the virus by Western blotting, with the lowest number of bands characteristic of the virus displayed by any sample being three. However, 39 and 48% of all patients exhibited no bands to p17 and p55 antigens, respectively, whereas 0 to 7.5% of all patients exhibited no bands to the other antigens. HIV-1 gag DNA sequences were detected in 117 (93.6%) of 125 cell pellets processed from the peripheral blood of these same patients. All eight patients initially negative by PCR tested positive when a second pellet which had been produced from the same blood sample was tested. Despite a decrease in antibody reactivity to HIV Gag and Pol proteins, patients with advanced HIV-1 infection remained positive for HIV-1 antibody by EIA and Western blot testing. Confirmation by the HIV-1 Western blot assay still appears to be the more sensitive assay for the diagnosis of HIV-1 infection in those individuals with advanced HIV-1 infection in the United States.
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PMID:Detection of human immunodeficiency virus type 1 (HIV-1) antibody by western blotting and HIV-1 DNA by PCR in patients with AIDS. 911 92

Thrombocytopenia is a common finding in infection with equine infectious anaemia virus (EIAV), a lentivirus with some homology to human immunodeficiency virus (HIV). The thrombocytopenia of EIA, like that in some HIV patients, appears to have a multifactorial pathogenesis. To investigate the decreased platelet production seen in experimental EIA, the levels of three potential negative regulators of platelet production--tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta) and interferon-alpha (IFN-alpha)--were measured in serum and bone marrow of six severe combined immunodeficient (SCID) foals and ten immunocompetent EIAV-infected foals. Levels of cytokines in pre-infection foal sera and bone marrow were compared with levels observed during clinical EIA. Mean serum levels of TNF-alpha and IFN-alpha were significantly higher (P < 0.05) on days -4 to 0 of thrombocytopenia than before infection. Serum TGF-beta was significantly elevated on all days except day -1 of thrombocytopenia. Bone marrow TNF-alpha levels were significantly increased in infected foals just before clinical thrombocytopenia. TGF-beta activity was not different in pre-infection and pre-thrombocytopenia bone marrows, but levels of TGF-beta protein as determined by immunohistochemical staining were significantly higher in pre-thrombocytopenia bone marrow. IFN-alpha activity in bone marrow increased just before thrombocytopenia, but the difference was not significant at P < 0.05. Serum TNF-alpha levels were 2-2.5 times higher in SCID foals on three of the days prior to thrombocytopenia than in immunocompetent foals. No significant differences were found between the levels in SCID and immunocompetent foals of serum and bone marrow TGF-beta or IFN-alpha at any of the times examined.
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PMID:Elevation of cytokines associated with the thrombocytopenia of equine infectious anaemia. 934 75

A neutralization enzyme immunoassay (N-EIA) was used to determine the neutralizing serum antibody titers to influenza A/Taiwan/1/86 (H1N1) and Beijing/353/89 (H3N2) viruses after vaccination of 51 human immunodeficiency virus (HIV) type 1-infected individuals and 10 healthy noninfected controls against influenza virus infection. Overall, the N-EIA titers correlated well with the hemagglutination-inhibition (HAI) titers that were observed in the same samples in a previous study (F. P. Kroon, J. T. van Dissel, J. C. de Jong, and R. van Furth, AIDS 8:469-476,1994). The N-EIA appeared to be more sensitive than the HAI test. Significantly more fourfold or higher rises in N-EIA titer and higher mean N-EIA titers occurred in HIV-infected individuals with > or =200 CD4+ cells per microl than in those with <200 CD4+ cells per microl.
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PMID:Comparison of neutralizing and hemagglutination-inhibiting antibody responses to influenza A virus vaccination of human immunodeficiency virus-infected individuals. 945 91

We developed an immunochromatographic whole-blood test (WBT) which detects antibodies to human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) from fingerstick blood. The sensitivity and specificity of the WBT were 99.41% (1,018 confirmed positive patients) and 99.89% (941 uninfected patients), respectively (enzyme immunoassay [EIA] on serum or plasma as a reference). WBT performance was comparable to those of licensed EIAs and Western blotting, using 18 HIV-2 sera, 23 HIV-1 seroconversion panels, and a low-titer performance panel (in lieu of whole blood).
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PMID:A simple whole-blood test for detecting antibodies to human immunodeficiency virus. 952 Nov 56

Equine infectious anemia virus (EIAV) is an ungulate lentivirus that is related to human immunodeficiency virus (HIV). Much of the understanding of lentiviral gene regulation comes from studies using HIV. HIV studies have provided insights into molecular regulation of EIAV expression; however, much of the regulation of EIAV expression stands in stark contrast to that of HIV. This review provides an overview of the current state of knowledge of EIAV regulation by comparing and contrasting EIAV gene regulation to HIV. The role of EIAV gene regulation is discussed in relation to EIAV pathogenesis.
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PMID:Regulation of equine infectious anemia virus expression. 957 May 9


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