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Query: UMLS:C0019693 (HIV)
 170,526 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A simplified application of the polymerase chain reaction (PCR) to the routine detection of human immunodeficiency virus type 1 (HIV-1) transcripts from peripheral lymphocytes of infected subjects is described. This technique is simpler than previously described assays and was shown to be highly sensitive after ethidium bromide staining of polyacrylamide gel electrophoresis of amplified material. The method can be used for the virologic evaluation of HIV-1-infected subjects, thus allowing early identification of seropositive patients with signs of active infection.
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PMID:Detection of human immunodeficiency virus type 1 transcripts in peripheral blood lymphocytes by the polymerase chain reaction. 171 62

The synthesis of 2-halo-9-(2-deoxy-2-fluoro-beta-D-arabinofuranosyl)adenines (4b and 4d) by coupling the 2,6-dihalopurine with 3-acetyl-5-benzoyl-2-deoxy-2-fluoro-D-arabinofuranosyl bromide (2) followed by replacement of the 6-halogen with concomitant removal of the acyl blocking groups is described. 2-Fluoroadenine derivative 4g had to be prepared by the diazotization-fluorination of 2-aminoadenine nucleoside 4e. All three nucleosides provided good increases in life span of mice inoculated with P388 leukemia. The best results were obtained when the compounds were administered q3h x 8 on days 1, 5, and 9 after implantation of the leukemia cells. The 2',3'-dideoxynucleoside 5b, prepared by deacetylation of 4f and deoxygenation of the resultant 4h followed by removal of the benzoyl group of 5a, was slightly active against HIV in cell culture.
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PMID:Synthesis and biologic activity of 2'-fluoro-2-halo derivatives of 9-beta-D-arabinofuranosyladenine. 173 56

A two-step polymerase chain reaction (PCR), with four double (nested) primer pairs, used for the detection of HIV-2 in clinical samples is described. With these four nested primer pairs we could detect HIV-2 DNA in 17 of 17 virus isolates and in blood mononuclear cell samples from 31 of 37 (83.7%) seropositive individuals after ethidium bromide staining of the amplified DNA. The nested primer PCR was also compared with a single primer pair-based PCR followed by hybridization. The sensitivities of the two methods were almost equal, but the nested primer PCR offered obvious technical advantages.
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PMID:Improved detection of HIV-2 DNA in clinical samples using a nested primer-based polymerase chain reaction. 174 Jul 55

Sera were obtained from 50 individuals infected with human immunodeficiency virus type 1 or from HIV-1-uninfected individuals before or after vaccination with recombinant gp160. These sera were evaluated for activity antagonistic to the cell-killing activity of the chimeric Pseudomonas exotoxin hybrid protein, sCD4-PE40. For these studies, Chinese hamster ovary (CHO) cells were transfected with a chimeric plasmid encoding the tat, rev, and envelope genes of HIV-1 and a cell line was selected for stable expression of the envelope glycoproteins at the cell surface (CHO-env). Cytotoxicity of sCD4-PE40 for CHO-env in the presence or absence of added human serum was quantitated spectrophometrically following enzymatic reduction of a tetrazolium bromide within the mitochondria of viable cells (MTT assay). Several HIV+ sera inhibited the cytotoxic activity of sCD4-PE40; the antagonist had properties consistent with those of immunoglobulins in that it was heat stable, absorbed by protein A, and reversible by increasing the concentration of sCD4-PE40. Of 15 HIV+ sera which strongly reacted with gp120, 11 (73%) also potently inhibited sCD4-PE40 cytotoxicity, and cytotoxicity was inhibited by sera from some HIV- individuals after, but not before, immunization with gp160. These data suggested a role for antibody to gp120 in the antagonistic activity. However, not all sera with antibody to gp120 antagonized sCD4-PE40 cytotoxicity and high levels of antagonist activity were frequently (40%) found in HIV+ sera lacking immunoblot-detectable antibody to gp120, or antibody to either CD4 or PE40. Grouping of the HIV+ sera according to the patients' absolute number of CD4+ cells revealed that the degree of inhibition of sCD4-PE40 cytotoxicity approached a Gaussian distribution, suggesting that persons with CD4+ cell counts between 200 and 700/mm3 may be more likely to possess significant levels of serum antagonist. This data have implications for the clinical development of sCD4-PE40 or other sCD4-based therapeutics in the management of HIV-1 infection.
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PMID:Soluble CD4-PE40 is cytotoxic for a transfected mammalian cell line stably expressing the envelope protein of human immunodeficiency virus (HIV-1), and cytotoxicity is variably inhibited by the sera of HIV-1-infected patients. 174 81

Two non-isotopic polymerase chain reaction (PCR) methods were evaluated by testing blood from 41 HIV-1-seropositive and 16 HIV-1-seronegative Ugandan mothers and 56 of their children (aged 0.5-15.0 months). Amplification of HIV-1 sequences was performed in duplicate using a biotinylated primer pair to the gag region (SK 462-431) and nested primer pairs (JA 17-20) to the pol region of HIV-1. gag sequences were hybridized using a microtiter plate coated with the SK 102 probe followed by colorimetric detection using an avidin-horseradish peroxidase conjugate and tetramethylbenzidine/peroxide substrate. pol sequences were detected on agarose gel stained with ethidium bromide. Results of HIV-1 PCR analysis showed that 40 out of 41 (98%) seropositive mothers and 10 out of 29 (34%) seropositive children had detectable HIV-1 gag and pol sequences. None of the 16 seronegative mothers nor 27 seronegative or Western blot-indeterminate children had detectable HIV-1 sequences. Our results suggest that non-isotopic PCR methods are sensitive, specific, and potentially useful in the early diagnosis of HIV-1 infection in developed and developing countries.
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PMID:Non-isotopic polymerase chain reaction methods for the detection of HIV-1 in Ugandan mothers and infants. 181 29

A solution hybridization assay using acridinium ester labelled probes is described for detection of amplified HIV-1 DNA segments. Amplification was achieved by 30 cycles of the polymerase chain reaction using SK38/SK39 primers specific for a constant region of the HIV-1 gag region together with HLA DQ alpha primers as internal control. Discrimination between hybridized and non-hybridized probes by differential hydrolysis resulted in a three log reduction of the chemiluminescence signal of the non-hybridized probe within 6 min without significant changes in the hybridized probes due to protection of the acridinium ester to hydrolysis by intercalation formation. Chemiluminescence was measured by a two-step-injection method with hydrogen-peroxide and NaOH. About 50 attomols of HIV-1 gag DNA could be detected. Chemiluminescence results, given in relative light units (RLU) of 159 HIV-1-infected patients (range 4013-458319) showed clear discrimination from 64 noninfected control samples (range 838-1477) (cut off 2000 RLU). Comparison with parallel detection of amplified products with autoradiography (32P) and ethidium bromide-stained agarose gels or a p24 antigen ELISA demonstrated better sensitivity and reproducibility of the chemiluminescence assay. The time required for the assay, including measurements, is less than 30 min, which allows reporting 'PCR results' on the same day.
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PMID:A rapid chemiluminescence detection method for PCR-amplified HIV-1 DNA. 187 18

A simple, sensitive and specific method using the polymerase chain reaction (PCR) for amplification of human immunodeficiency virus type 1 (HIV-1) is described. The method involves minimal manipulations. Peripheral blood mononuclear cells (PBMC) were prepared by a rapid Ficoll-Paque gradient method. Lymphocytes were lysed in PCR buffer containing Proteinase K and detergents, and subjected to amplification under stringent conditions, using two primer pairs. Amplified DNA sequences were hybridized with a 3'-end labelled probe, electrophoresed on agarose gels and visualised by ethidium bromide staining. Identification of amplified HIV-1 proviral DNA sequences was confirmed by autoradiography. HIV-1 sequences were amplified in all samples from 103 HIV-1 seropositive individuals, but not in 40 HIV-1 seronegative controls. The absence of contamination may be attributable in part to minimisation of manipulations before amplification.
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PMID:A simple and rapid method for detecting human immunodeficiency virus by PCR. 187 20

An enzyme immunoassay was developed to detect human immunodeficiency virus type 1 (HIV-1) DNA amplified by polymerase chain reaction (PCR-EIA). A set of primers (outer set) was used in PCR to amplify a segment of the HIV-1 gag gene from peripheral blood mononuclear cells. Hybrids between the amplified DNA and a RNA probe were measured in a microtiter plate immunoassay using a beta-D-galactosidase-conjugated monoclonal antibody to DNA-RNA hybrids and a fluorescent substrate. A second set of primers (nested set) located within the outer set was used in PCR with a known template to prepare the probe. One primer of the nested set included the T7 RNA polymerase promoter at its 5' end allowing transcription of a single-stranded RNA probe. Ten copies of HIV-1 DNA could be detected by PCR-EIA (42 fluorescent units with a background of 18 fluorescent units) compared with a detection limit of 1000 copies by ethidium bromide-stained agarose gel. HIV-1 DNA was detected by PCR-EIA in peripheral blood mononuclear cells from 32 of 33 seropositive patients (range 54-810 fluorescent units), and 0 of 25 seronegative patients (range 20-40 fluorescent units) (sensitivity 97%; specificity 100%). PCR-EIA offers a practical and nonisotopic method to objectively measure PCR-amplified HIV-1 DNA and has the potential for the measurement of other microbial pathogens in human body fluids.
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PMID:Enzyme immunoassay for detection of hybrids between PCR-amplified HIV-1 DNA and a RNA probe: PCR-EIA. 174 86

A simple, sensitive, and specific polymerase chain reaction (PCR) protocol for the detection of human immunodeficiency virus type 1 (HIV-1) is described. We have improved all three PCR steps: sample preparation, DNA amplification, and detection of the amplified product. Some of the improvements have been described previously, but they have never been combined into a complete PCR protocol. Peripheral blood mononuclear cells were lysed directly in a buffer containing sodium dodecyl sulfate, Triton X-100, and proteinase K. This crude cell lysate was amplified in a two-step PCR, first with outer primers and then with inner primers nested within the first primers. The PCR product was visualized by agarose gel electrophoresis and ethidium bromide staining. Thus, we avoided conventional DNA extraction as well as hybridization for the detection of the PCR product. The samples were analyzed with four sets of nested primers (JA4 through JA7, JA9 through JA12, JA13 through JA16, and JA17 through JA20) designed to amplify HIV-1 gag, env gp120, env gp41, and pol sequences, respectively. We were able to amplify HIV-1 sequences in all samples from 90 HIV-1-seropositive individuals with mostly mild symptoms. Of these individuals, 24 were negative in HIV-1 isolation and 9 were selected because they were infected by African and Haitian HIV-1 strains. Eighty-five (94%) individuals were positive with at least three of four primer sets. Samples from 26 healthy blood donors, as well as cells infected in vitro with human immunodeficiency virus type 2 and human T-cell leukemia virus type I, were negative in PCR, thus demonstrating the specificity of the amplification.
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PMID:Simple, sensitive, and specific detection of human immunodeficiency virus type 1 in clinical specimens by polymerase chain reaction with nested primers. 238 Mar 80

A rapid, sensitive and automated assay procedure was developed for the in vitro evaluation of anti-HIV agents. An HTLV-I transformed T4-cell line, MT-4, which was previously shown by Koyanagi et al. (1985) to be highly susceptible to, and permissive for, HIV infection, served as the target cell line. Inhibition of the HIV-induced cytopathic effect was used as the end point. The viability of both HIV- and mock-infected cells was assessed spectrophotometrically via the in situ reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The procedure was optimized as to make optimal use of multichannel pipettes, microprocessor-controlled dispensing and optical density reading. The absorbance ratio of the mock-infected control to the HIV-infected samples was about 20. This allowed an accurate determination of the 50% effective doses, as demonstrated for 3'-azido-2',3'-dideoxythymidine (AZT), 2',3'-dideoxycytidine (ddCyd), dextran sulfate and heparin. The technique significantly reduced labor time as compared to the trypan blue exclusion method, and permits the evaluation of large numbers of compounds for their anti-HIV activity.
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PMID:Rapid and automated tetrazolium-based colorimetric assay for the detection of anti-HIV compounds. 246 Apr 79


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