HIV Reverse Transcriptase (hiv + reverse_transcriptase)

Distribution by Scientific Domains


Selected Abstracts


Tetrazole Thioacetanilides: Potent Non-Nucleoside Inhibitors of WT HIV Reverse Transcriptase and Its K103N Mutant.

CHEMINFORM, Issue 33 2006
Ester Muraglia
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]


Alcohol Suppresses IL-2,Induced CC Chemokine Production by Natural Killer Cells

ALCOHOLISM, Issue 9 2005
Ting Zhang
Background: Natural killer (NK) cells are a critical component of the host innate immune system. We investigated whether alcohol impairs NK cell function, particularly production of CC chemokines induced by interleukin (IL)-2, the natural ligands for CCR5 receptor. Methods: Primary NK cells and NK cell line (YTS) were cultured with or without alcohol (10 to 80 mM) for three hours. The culture supernatants were then harvested and used to treat human peripheral blood monocyte-derived macrophages and a HeLa cell line, which expresses CD4, CCR5, and CXCR4 receptors (MAGI cells). CC chemokine expression by YTS and primary NK cells treated with or without alcohol was analyzed with the real-time RT-PCR and ELISA. Ca2+i and Western blot assays were used to determine calcium-mediated intracellular signaling pathway and NF-,B p65 expression. HIV strains (Bal and UG024) were used to infect macrophages and MAGI cells. In addition, ADA (macrophage-tropic strain) and murine leukemia virus (MLV) envelope-pseudotyped HIV infection was carried out in macrophages. HIV infectivity was determined by HIV reverse transcriptase (RT) and ,-galactosidase activity assays. Results: Alcohol inhibited IL-2,induced CC chemokine (CCL3 and CCL4) expression by NK cells. Functional tests demonstrated that this reduced expression of CC chemokines was associated with diminished anti-HIV ability of NK cells. Alcohol also reduced the ability of NK cells to response to CCL3-mediated chemotaxis. Alcohol inhibited IL-2,induced NF-,B p65 protein expression and calcium mobilization by NK cells. Conclusions: Alcohol, through the inhibition of IL-2,induced NF-,B p65 protein expression and intracellular calcium mobilization, suppressed NK cell production of CC chemokines. This suppression of CC chemokine production was associated with diminished anti-HIV activity of NK cells. Thus, by inhibiting NK cell,mediated innate immunity against HIV, alcohol consumption may have a cofactor role in the immunopathogenesis of HIV disease. [source]


Simultaneous determination of endogenous deoxynucleotides and phosphorylated nucleoside reverse transcriptase inhibitors in peripheral blood mononuclear cells using ion-pair liquid chromatography coupled to mass spectrometry

PROTEOMICS - CLINICAL APPLICATIONS, Issue 10-11 2008
Leon Coulier
Abstract Nucleoside reverse transcriptase inhibitors (NRTIs) are activated intracellularly to their triphosphate (TP) form, which compete with endogenous deoxynucleotide-triphosphates (dNTP) as substrate for HIV reverse transcriptase. The activity of NRTIs is thus described by the NRTI-TP-to-dNTP ratio in relevant cell types. Therefore, we developed an ion-pair (IP) LC-MS method for the simultaneous analysis of the mono-, di-, and TP forms of NRTIs and endogenous deoxynucleosides in peripheral blood mononuclear cells (PBMC). The IP-LC method was applied on an IT mass spectrometer using the MS-mode as well as on a triple quadrupole mass spectrometer using the MS/MS mode. The MS/MS approach on the triple quadrupole mass spectrometer demonstrated the best clinical applicability due to its higher sensitivity. The LOD (minimum amount on column) were 25,fmol for the TP forms of zidovudine, lamivudine, and stavudine, as well as for their endogenous dNTP counterparts. The linearity (R2) of the calibration curves were>0.99. The obtained LOD readily allow for clinical applications using just one million PBMC obtained from HIV-infected patients under therapy. [source]


Prevalence of drug resistance and newly recognised treatment-related substitutions in the HIV-1 reverse transcriptase and protease genes from HIV-positive patients naïve for anti-retrovirals

CLINICAL MICROBIOLOGY AND INFECTION, Issue 9 2004
C. Torti
Abstract The aim of this study was to assess the prevalence of genetic changes in either the HIV reverse transcriptase (RT) or protease (Pro) genes in a cohort of patients naïve for anti-retroviral therapy. Of 61 patients, 43 (70.5%) were infected with HIV strains harbouring at least one resistance-related mutation, with 41 (67.2%) harbouring newly recognised treatment-related mutations. Among the 61 patients, the prevalence of specific mutations in the RT gene was as follows: 39A, 1.6%; 43E, 1.6%; and 228H, 1.6%. The prevalence of specific mutations in the Pro gene was as follows: 11I, 1.6%; 13V, 26.2%; 35D, 19.6%; 45R, 1.6%; 58E, 1.6%; 62V, 31%; 72V, 11.4%; 72M, 6.5%; 72T, 3.2%; 75I, 1.6%; and 89M, 13%. A higher prevalence of newly recognised mutations was found in strains from patients infected through sexual practices (30/36 = 83.4% vs. 11/25 = 44%; p 0.0023; OR 10.91; 95% CI 3.14,40.39). These findings support the use of resistance testing in patients naïve for anti-retroviral therapy, and suggest that the possible impact of newly recognised treatment-related mutations on clinical outcome requires further investigation. [source]