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)

Molecularly cloned simian immunodeficiency viruses capable of inducing acute, fatal disease in pig-tailed macaques had been derived previously from a biological clone (bcl-3) of the PBj14 isolate of SIV from sooty mangabey monkeys (SIVsmmPBj14). The present study was undertaken in order to characterize virus from a second biological clone of SIVsmmPBj14, bcl-1, which fails to induce acute or fatal disease. Polymerase chain reaction was used to amplify 5' and 3' viral genome halves. The DNA sequence of two 3' halves was determined, and an infectious recombinant generated using a bcl-3-derived 5' half and a bcl-1-derived 3' half. Overall, bcl-1- and bcl-3-derived viruses displayed close homology, differing by a total of 2% at the DNA level and 1-6% at the amino acid level within the 8 open reading frames examined. In contrast to the bcl-3-derived viruses, the bcl-1-derived viruses encode a truncated transmembrane envelope glycoprotein. Another consistent difference was the presence of a 22 bp duplication in the U3 portion of the long terminal repeat (LTR) of bcl-3-derived viruses that includes the NF-kappa B transcriptional enhancer binding site. To assess the importance of this duplication, virus chimeras were generated which removed the duplication from the 3'-LTR or from both LTRs of a bcl-3 clone. The former virus was unstable, reacquiring the duplication through recombination with the 5' LTR. No consistent difference were observed, however, between viruses with or without the duplication in the in vitro studies conducted to date.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Molecular clones from a non-acutely pathogenic derivative of SIVsmmPBj14: characterization and comparison to acutely pathogenic clones. 150 26

Requirements for the establishment of productive infection with the human immunodeficiency virus type 1 (HIV-1) in primary monocytes were investigated. In vitro, monocytes rendered susceptible for infection after at least a 2-d culture, but when cultured in the presence of differentiation-inducing agent IL-4, accelerated susceptibility was seen. Complete resistance to HIV-1 infection was observed in monocytes that had been treated for 5 d with rIL-4, and comparable results were obtained with other differentiation inducers such as dexamethasone or 1,25(OH)2 vitamin D3 (1,25(OH)2vitD3). The inhibition of productive infection was not caused by downregulation of CD4 expression or HIV-1 transcription, nor by intracellular accumulation of virions. Since treatment with rIL-4, dexamethasone, or 1,25(OH)2vitD3 also resulted in complete inhibition of monocyte proliferation, we studied whether establishment of productive infection in monocytes is proliferation dependent. Irradiation or mitomycin-C treatment within 24 h after inoculation prevented productive HIV-1 infection of monocytes, suggesting a proliferation-dependent step early in the virus replication cycle. Polymerase chain reaction (PCR) analysis revealed the presence of only incomplete proviral DNA species in non-proliferating monocytes, indicating restriction of viral replication at the level of reverse transcription. Thus, in analogy with HIV-1 infection of CD4+ T cells, proliferation of monocytes during differentiation into macrophages is a prerequisite for productive infection with HIV.
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PMID:Proliferation-dependent HIV-1 infection of monocytes occurs during differentiation into macrophages. 155 79

Polymerase chain reaction (PCR) DNA quantitation (PDQ) susceptibility testing rapidly and directly measures nucleoside sensitivity of human immunodeficiency virus type 1 (HIV-1) isolates. PCR is used to quantitate the amount of HIV-1 DNA synthesized after in vitro infection of peripheral blood mononuclear cells. The relative amounts of HIV-1 DNA in cell lysates from cultures maintained at different drug concentrations reflect drug inhibition of virus replication. The results of PDQ susceptibility testing of 2- or 3-day cultures are supported by assays measuring HIV-1 p24 antigen production in supernatants of 7- or 10-day cultures. DNA sequence analyses to identify mutations in the reverse transcriptase gene that cause resistance to 3'-azido-3'-deoxythymidine also support the PDQ results. With the PDQ method, both infectivity titration and susceptibility testing can be performed on supernatants from primary cultures of peripheral blood mononuclear cells. PDQ susceptibility testing should facilitate epidemiologic studies of the clinical significance of drug-resistant HIV-1 isolates.
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PMID:Susceptibility testing by polymerase chain reaction DNA quantitation: a method to measure drug resistance of human immunodeficiency virus type 1 isolates. 156 15

The principal neutralizing epitope of the human immunodeficiency virus type 1 (HIV-1) lies between two invariant cysteines in the third variable region (V3) of the viral envelope (gp120), and its amino acid sequence varies among different HIV-1 isolates. HIV-2 carries an analogous amino acid sequence between two cysteines of the V3 regions, but its functional similarity with the HIV-1 principal neutralizing epitope is uncertain. We studied the degree of genetic variation of the HIV-2 V3 region in fresh blood samples from 12 HIV-2-seropositive individuals from Guinea-Bissau. Polymerase chain reaction was used to amplify viral fragments of 465 bp containing the V3 region from cellular DNA. Nucleotide sequence analysis of the entire envelope fragment from each patient revealed that the degree of variation among field isolates of HIV-2 is comparable to that observed in the analogous region of HIV-1. Most of the HIV-2 isolates studied were highly related, suggesting the existence of a limited number of different viral strains in the cohort studied. Thus, the HIV-2 and HIV-1 V3 regions vary to a similar degree and may also have analogous functions.
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PMID:In vivo genetic variability of the human immunodeficiency virus type 2 V3 region. 160 60

Polymerase chain reaction (PCR) testing using up to four primer pairs and biotinylated probes was 97.9% sensitive (188 of 192 specimens positive) and 100% specific (267 of 267 specimens negative) for detecting the presence or absence of human immunodeficiency virus (HIV) DNA in peripheral blood mononuclear cells from pediatric patients whose HIV status has been confirmed. SK38/39 and SK145/150 were the most sensitive primer pairs, respectively detecting HIV DNA in 95.6 and 95.9% of peripheral blood mononuclear cell specimens from HIV-infected children and collectively detecting all adequately tested PCR-positive specimens. Primer pairs SK29/30 and SK68/69 respectively detected HIV DNA in only 76.4 and 76.6% of HIV-positive specimens. Among infants born to HIV-seropositive mothers, 30 who subsequently were confirmed to be infected were sampled when they were less than or equal to 6 months of age; in all but one infant, HIV DNA was found in the first specimen collected. Among the nine youngest infected infants tested, all were PCR positive by 38 days of age. PCR methods thus have reliably detected vertically transmitted HIV infection early in life.
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PMID:Detection of human immunodeficiency virus type 1 infection in young pediatric patients by using polymerase chain reaction and biotinylated probes. 173 67

Polymerase chain reaction (PCR) identified regions of the gag, LTR, and env genes of human immunodeficiency virus type 1 (HIV-1) in 5 (13%) of 38 high-risk homosexual men who were negative for HIV-1 antibodies by Western blot (WB). Significant increases in CD8+ cells, particularly those bearing activation CD8+CD38+ and CD8+Ia+ antigens, and marked reductions in CD4+ cells were detected in WB-PCR+ subjects compared with 33 WB-PCR- homosexuals. WB-PCR+ subjects had impaired B cell but not T cell functions. Immunologic characteristics of WB-PCR+ homosexuals were indistinguishable from those of 17 WB+PCR+ subjects. Subjects progressing from WB-PCR- to WB-PCR+ to WB+PCR+ showed sequential phenotypic and functional alterations in their B and T cell compartments. These changes and the presence of HIV-1 genomic sequences were the first indications of HIV-1 infection and together with p24 antigenemia signified an inevitable progression to AIDS.
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PMID:Human immunodeficiency virus type 1 (HIV-1) genomic sequences and distinct changes in CD8+ lymphocytes precede detectable levels of HIV-1 antibodies in high-risk homosexuals. 182 6

Concentrated tissue culture pellets infected with human immunodeficiency virus (HIV) containing 1 x 10(7) cells/ml were vaporized by means of a carbon dioxide laser. The vaporous debris resulting from the laser's impact were evacuated through sterile silastic tubing, then bubbled through sterile culture medium (RPMI) positioned in series with a commercial smoke evacuator. No HIV DNA was detected in the culture medium flask. Tissue culture studies of the silastic collection tubing revealed p24 HIV gag antigen in 3 of 12 tube segments at the end of 1 week and in 1 of 12 tube segments at 2 weeks. No sustained infection of HIV cultured cells was observed at the 28th day. Polymerase chain reaction (PCR) analysis of particulate debris obtained from the silastic collection tubing was positive from proviral HIV DNA in both immediately sampled and day 14 cultured material.
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PMID:Presence of human immunodeficiency virus DNA in laser smoke. 190 45

Polymerase chain reaction techniques were used to identify simian immunodeficiency virus (SIV) SIVsmm gag sequences in genomic DNA isolated from peripheral blood mononuclear cells from naturally infected asymptomatic seropositive and seronegative sooty mangabeys (Cercocebus atys) and from experimentally infected but asymptomatic rhesus macaques (Macaca mulatta). The results indicate that most if not all SIV-seronegative mangabeys from the colony at the Yerkes Primate Center are in fact infected with SIVsmm despite their lack of humoral immune response, confirming previous immunological and virological observations made by our laboratory. Sequence analysis of these particular gag fragments from the mangabey revealed an average of 88% nucleotide sequence homology but 97% amino acid identity with the previously published sequence of the SIVsmmH4 clone. The significance of this finding relative to the asymptomatic state of SIV-infected mangabeys and disease-susceptible SIV-infected rhesus macaques is discussed.
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PMID:Detection of occult simian immunodeficiency virus SIVsmm infection in asymptomatic seronegative nonhuman primates and evidence for variation in SIV gag sequence between in vivo- and in vitro-propagated virus. 200 46

Polymerase chain reaction (PCR) was used to amplify a long sequence of human immunodeficiency virus (HIV) DNA, to assess the correlation between PCR signal and clinical stage of disease, and to demonstrate the genotypic variability of different HIV isolates. Twenty-four (96%) of 25 anti-HIV-reactive patients and none of 12 controls were positive for HIV proviral DNA by PCR. After quantification of the PCR signal, a significant difference in the relative amount of HIV proviral DNA per 10(5) peripheral blood mononuclear cells between symptomatic patients (Centers for Disease Control [CDC] class IV) (32,284 +/- 5225 cpm [mean +/- SE], equivalent to 802 HIV plasmid DNA copies) and patients without symptoms (CDC class II/III) (5484 +/- 1469 cpm [mean +/- SE], equivalent to 67 HIV plasmid DNA copies) was observed (P less than .01). Restriction analysis of PCR products in selected samples showed extensive genetic polymorphism between different isolates and more than one viral genotype per isolate. There was a clear correlation between the appearance of clinical symptoms in HIV infection and high levels of viral replication.
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PMID:Clinical correlation and genetic polymorphism of the human immunodeficiency virus proviral DNA obtained after polymerase chain reaction amplification. 223 Feb 30

The present study was undertaken to establish the incidence of t(14;18) (q32:q21) chromosomal translocations detectable by a polymerase chain reaction (PCR) assay on fixed lymphoma biopsies. DNA samples from 113 formalin-fixed, paraffin-embedded tissue biopsies (non-Hodgkin's lymphomas, 96 cases; Hodgkin's disease, six cases; reactive, 11 cases) were amplified by the PCR. Of the 96 non-Hodgkin's lymphoma cases, 56 had a follicular pattern and 40 had a diffuse pattern. Polymerase chain reaction-amplifiable t(14;18) chromosomal translocations were detected in 23 of 43 follicular low-grade lymphomas, one of eight follicular intermediate grade lymphomas, one of five follicular high-grade lymphomas, and one of 10 diffuse large-cell lymphomas. The remaining 30 diffuse lymphomas represented the spectrum of the Working Formulation classification. There were six biopsy specimens of Hodgkin's disease and 11 biopsy specimens of follicular hyperplasia; all were negative. The translocation was not detected in 16 biopsies (non-Hodgkin's lymphomas, seven cases; follicular hyperplasia, nine cases) from patients infected with the human immunodeficiency virus. Since this procedure uses the widely available fixed paraffin-embedded material, correlative studies between histology and genetic aberrations can be readily undertaken.
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PMID:Detection of specific t(14;18) chromosomal translocations in fixed tissues. 230 46


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