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 have used a human immunodeficiency virus type 1 (HIV-1)-specific IgG-Fc capture enzyme immunoassay (IgG-CEIA) to elucidate the dynamics of HIV-1 maternal antibody decay and de novo synthesis of HIV-1 antibodies in infants. Two hundred and thirty-nine serum specimens from 77 infants were analyzed by the IgG-CEIA and by two different conventional EIAs. With the IgG-CEIA, IgG was captured by an anti-human IgG monoclonal antibody (3C8) that reacts with all subclasses and was detected by recombinant HIV-1 envelope protein (CBre3)-peroxidase conjugate. Unlike the conventional EIAs, the IgG-CEIA showed a rapid decay of HIV-1-specific antibody in uninfected infants, with decline to background levels by 6 months (T1/2 [half-life] = 28-30 days). All 69 specimens collected from 39 uninfected infants between 6 and 15 months of age were negative by IgG-CEIA. However, HIV-1 antibodies remained high in infected infants; 20/22 infants (90.9%) with specimens between the ages of 6 to 23 months were positive by IgG-CEIA. Subtracting mean IgG-CEIA optical density values of seroreverting infants from those of HIV-1-infected infants in corresponding age groups provided a model for seroconversion in infected infants, with detectable IgG antibody synthesis starting about 3 months after birth. The IgG-CEIA may be a simple and important tool for early diagnosis of HIV-1 infection in infants at 6 months of age.
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PMID:Dynamics of maternal IgG antibody decay and HIV-specific antibody synthesis in infants born to seropositive mothers. The NYC Perinatal HIV Transmission Study Group. 825 38

The Tat protein of human immunodeficiency virus 1 (HIV-1) can enter cells efficiently when added exogenously in tissue culture. To assess if Tat can carry other molecules into cells, we chemically cross-linked Tat peptides (residues 1-72 or 37-72) to beta-galactosidase, horseradish peroxidase, RNase A, and domain III of Pseudomonas exotoxin A (PE) and monitored uptake colorimetrically or by cytotoxicity. The Tat chimeras were effective on all cell types tested, with staining showing uptake into all cells in each experiment. In mice, treatment with Tat-beta-galactosidase chimeras resulted in delivery to several tissues, with high levels in heart, liver, and spleen, low-to-moderate levels in lung and skeletal muscle, and little or no activity in kidney and brain. The primary target within these tissues was the cells surrounding the blood vessels, suggesting endothelial cells, Kupffer cells, and/or splenic macrophages. Tat-mediated uptake may allow the therapeutic delivery of macromolecules previously thought to be impermeable to living cells.
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PMID:Tat-mediated delivery of heterologous proteins into cells. 829 May 79

An enzyme-linked oligosorbent assay (ELOSA) was developed for the detection on microtiter plates of polymerase chain reaction (PCR)-amplified human immunodeficiency virus type 1 (HIV-1) DNA. The denatured PCR product was hybridized with a passively adsorbed oligonucleotide capture probe and a horseradish peroxidase-labeled oligonucleotide detection probe. The sensitivity and specificity of the PCR-ELOSA technique depended to some extent on the nucleotide sequences of the oligonucleotide primer and probe quartet used in the amplification and detection. We evaluated five oligonucleotide quartets located in the gag, pol, vpr, env, and nef regions of HIV-1. DNAs from 39 HIV-1-seropositive individuals and 27 healthy HIV-1-seronegative controls were amplified by the PCR procedure, and the products were detected by ELOSA. Ten copies of HIV-1 DNA against a background of 1 microgram of human DNA were specifically detected by PCR-ELOSA. Specificities and sensitivities were, respectively, 100 and 95% for the gag system, 100 and 97% for the pol system, 100 and 85% for the vpr system, 96 and 95% for the env system, and 100 and 95% for the nef system. The simplicity of ELOSA makes it suitable for automation and applicable to genetic testing and detection of viral and bacterial DNAs or RNAs in most routine laboratories.
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PMID:Enzyme-linked oligosorbent assay for detection of polymerase chain reaction-amplified human immunodeficiency virus type 1. 831 84

We have developed a simple gene quantification system using the competitive polymerase chain reaction (CPCR) followed by microtiter format analysis. CPCR is carried out using a mutant competitor with the same size as the target DNA product, and a minimal base exchange to insure the same amplification kinetics. One primer is aminated at the 5' end to produce PCR products that are captured onto carboxylated wells of microtiter plates through peptide bond formation. The non-aminated DNA strands are stripped off from the wells by alkali washing, and the remaining aminated strands are hybridized with either a digoxigenin-labeled wild type-specific oligonucleotide probe or a competitor-specific probe. To standardize the hybridization conditions of the probes, a DNA construct containing wild type and mutant competitor sequences in tandem is captured at different concentrations, hybridized with the probes, and used to generate a standard curve. Bound probes are detected by anti-digoxigenin antibody conjugated with peroxidase and chromogen. Optical densities are recorded with a conventional microtiter plate reader and converted to concentrations according to the standard curves. The ratios of wild type DNA to mutant competitor are used to determine the initial amounts of wild type DNA in the samples. This method was used successfully to quantify human immunodeficiency virus type 1 (HIV-1) env gene in human lymphocytes. It only requires a thermal cycler and a conventional microtiter plate reader, and can be readily done on a large scale. Potential applications include detection of other pathogens, diagnosis of genetic disorders and studies of gene expression.
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PMID:Microtiter format gene quantification by covalent capture of competitive PCR products: application to HIV-1 detection. 834 24

Glucose oxidase and peroxidase (lactoperoxidase or myeloperoxidase) are virucidal to human immunodeficiency virus type 1 (HIV-1) in the presence of sodium iodide, as assessed by the loss of viral replication in a syncytium-forming assay or by the inhibition of cytopathic effects on infected cells. In the presence of low concentrations of sodium iodide, five HIV-1 isolates were equally susceptible to this virucidal system at enzyme concentrations of a few milliunits. The loss of viral replication was linearly related to the time of incubation in the enzyme solutions, with an inactivation rate of 1 log unit every 30 min. These enzymes and this halide were also cytotoxic to chronically infected, but not to uninfected, cultured CEM cells. Protein conjugates were prepared by using the enzymes and murine antibody 105.34, which recognized the V3 loop of HIV-1 LAI isolate surface glycoprotein, or recombinant human CD4. The protein conjugates inactivated free virus at rates similar to those of the free enzymes and were more effective than antibody or recombinant CD4 alone. These in vitro findings demonstrate that the peroxidase-H2O2-halide system provides potent virucidal activity against HIV-1.
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PMID:Virucidal effects of glucose oxidase and peroxidase or their protein conjugates on human immunodeficiency virus type 1. 838 38

A double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) is described for the detection of Plasmodium falciparum antigen. The test is based on an immunoglobulin (Ig) M capture monoclonal antibody on the solid phase and an IgG monoclonal antibody conjugated to peroxidase. The simple test takes about 2.5 h to complete and, because it uses whole blood with no prior treatment, it is possible to process batches of 50-100 samples simultaneously. The test is specific to P.falciparum and has a sensitivity close to that usually achieved with Giemsa-stained blood films. The reagents employed are stable at refrigerator temperatures for over 6 months, and as the test is compatible with human immunodeficiency virus and hepatitis B surface antigen ELISAs it could be suitable for blood transfusion screening.
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PMID:The development and validation of a simple antigen detection ELISA for Plasmodium falciparum malaria. 846 87

The pattern of expression of GFAP immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (SIV). Blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. Strong GFAP immunoreactivity was found in astrocytic cells in both uninfected and SIV-infected juvenile macaque in the subpial cerebral cortex and in subcortical white matter, where GFAP-positive cells were abundant. GFAP staining of cortical layers 2-6 on the other hand was weak or absent in three uninfected controls and one infected animal without cognitive impairment, but moderate to strong in animals productively infected with SIV that demonstrated cognitive and/or motor impairment. These data demonstrate a cortical locus of astrocytic activation in rhesus monkeys infected with primate immunodeficiency virus isolate SIVB670 which, like HIV-1 in man, causes motor/cognitive impairment as well as immunodeficiency disease.
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PMID:Cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus. 847 48

A colorimetric reverse transcriptase assay (cRT assay) was developed for quantitative detection of HIV-1. In this format, reverse transcriptase incorporates biotin-labeled dUTP onto oligo-dT primers hybridized to poly A templates. The templates are covalently bound to the surface of microtiter wells. The amount of incorporated biotin-labeled dUTP is measured by binding horseradish peroxidase conjugated streptavidin, washing away unbound peroxidase, adding colorimetric substrate and then reading with a standard colorimetric reader. The sensitivity of the assay is very good. As little as 3 x 10(5) molecules of recombinant HIV-RT can be detected after 20 h of reaction time. Direct comparison using 3 cultured clinical isolates indicates that this level of detection is equivalent to the commercially available p24 antigen capture assay and the HIV-RNA assay based on branched DNA signal amplification. Other retroviruses, such as HIV-2 and feline immunodeficiency virus (FIV), can also be detected in this format. This non-isotopic assay is easy to perform and could provide a convenient and quantitative method for HIV study by monitoring reverse transcriptase, an essential activity in the infection process.
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PMID:Poly A-linked non-isotopic microtiter plate reverse transcriptase assay for sensitive detection of clinical human immunodeficiency virus isolates. 860

Using flow cytometry, we studied the expression of the CD4 antigen within the different cells present in human ejaculate, both in spermatozoa and round cells. In all, 20 samples of semen were obtained from fertile males; in 11 of these, we detected the presence of leukocytes, using the peroxidase test. Swim-up was performed for the analysis of the spermatozoa. From our results it may be concluded that there is no expression of the CD4 antigen on the surface of human spermatozoa or on CD45- ejaculate cells (epithelial and germinal cells). However, we did detect the presence of the CD4 antigen on the surface of the leukocyte cells (CD45+). A better characterization of these CD45+ cells made it apparent that the CD4+ cells of ejaculate are composed of T lymphocytes (helper/inducer T lymphocytes) and monocytes. Thus we may conclude that human spermatozoa do not express the CD4 antigen, the cell surface receptor for human immunodeficiency virus. However, we did detect CD4+ T lymphocytes and CD4+ monocytes in semen.
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PMID:CD4+ cells in human ejaculates. 874 46

Bio-normalizer, a natural Japanese health food prepared by the fermentation of Carica papaya, exhibits therapeutic properties against various pathologies including tumors and immunodeficiency. To understand the mechanism of bio-normalizer's therapeutic effects, we studied its action on the production of active oxygen species in cell-free systems (the Fenton reaction, the xanthine-xanthine oxidase system, and the hydrogen peroxide-hypochloride or hydrogen peroxide-horseradish peroxidase systems) and by human blood neutrophils and erythrocytes and rat peritoneal macrophages. Bio-normalizer efficiently inhibited the formation of oxygen radicals in cell-free systems and partly decreased spontaneous and menadione-stimulated superoxide production by erythrocytes, but manifested both stimulatory and inhibitory effects on oxygen radical release by dormant and activated phagocytes (neutrophils and macrophages). We suggest that bio-normalizer is able to enhance the intracellular production of innocuous superoxide ion and, at the same time, to diminish the formation of reactive hydroxyl radicals, perhaps by the inactivation of ferrous ions, the catalysts of the superoxide-driven Fenton reaction. We also propose that the normalization of an organism's superoxide level is one of the molecular mechanisms of bio-normalizer activity.
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PMID:Effects of bio-normalizer (a food supplementation) on free radical production by human blood neutrophils, erythrocytes, and rat peritoneal macrophages. 874 24


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