Biomedical subjects

Daniela Mologni

Publications and source records attributed to Daniela Mologni.

3 recordsLinked to original sources

PubMed2006

Vpr and HIV-1 disease progression: R77Q mutation is associated with long-term control of HIV-1 infection in different groups of patients.

BACKGROUND: Vpr (viral protein R) is a 96 amino acids soluble protein that is expressed late during viral replication. Recent studies have focused on the role of a mutation at position 77 that might be associated with the condition of long-term non-progression, but data are still controversial. PATIENTS AND METHODS: Fifteen long-term non-progressors (LTNP), 19 therapy-naive HIV-1-infected patients with progressive disease (Pr), 23 HIV-1-infected patients receiving sub-optimal therapy with dual nucleoside [nucleoside reverse transcriptase inhibitor (NRTI)] therapy but efficiently controlling viral replication (STP) and 19 antiretroviral therapy multi-experienced patients with actively replicating virus (MEP) were analysed. HIV-RNA was extracted from plasma samples, the Vpr region was amplified, cloned and sequenced. The Pol gene was amplified, directly sequenced and analysed using Sequence Navigator software. RESULTS: A significantly higher prevalence of the R77Q mutation was evidenced both in LTNP (86.7%) and STP (73.9%) in comparison with Pr (42.1%) and MEP (42.1%), (P = 0.007). Comparing groups of patients with progressive disease (Pr + MEP) and groups with non-progressive disease (LTNP + STP) the probability of harbouring the R77Q mutation was significantly higher in non-progressors (odds ratio, 5.16; P = 0.001). CONCLUSIONS: Our results support the hypothesis of the association of R77Q mutation in the Vpr gene with delayed progression of HIV-1 disease. R77Q does not seem to be linked to a particular viral strain but might be associated to immunologic selection. The R77Q mutation might reduce CD4+ T-cell depletion possibly affecting T-cell survival in vivo by altering the pro-apoptotic activity of Vpr.

Adult↗

PubMed2005

Increased CD36 expression on circulating monocytes during HIV infection.

BACKGROUND: Metabolic alterations and abnormalities of fat distribution are common findings in antiretroviral-treated HIV-1-infected patients. CD36 is a multifunctional receptor with a wide tissue distribution that plays a crucial role in the cellular uptake and metabolism of lipids. OBJECTIVES: To define the level of CD36 expression on circulating monocytes from HIV-1-infected patients and healthy controls (HCs) and to correlate CD36 expression levels with metabolic and immunovirologic parameters. METHODS: CD36 expression on peripheral blood monocytes was measured by means of flow cytometry in 165 HIV-1-infected patients and in 35 HCs. Statistical analysis was performed by means of univariate and multivariate analysis of variance models. RESULTS: CD36 expression was significantly higher in HIV-1-infected patients compared with HCs (P < 0.0001). HIV-1 infection was the only variable associated with CD36 expression on multivariate analysis, whereas no correlation was found between CD36 level and age, sex, body mass index, lipid serum levels, HIV RNA levels, time on antiretroviral therapy, or kind of antiretroviral regimen. CONCLUSIONS: HIV-1 infection is associated with increased expression of CD36 on circulating monocytes, and antiretroviral drugs play only a minor role in the complex homeostasis of this receptor. Given its role in the cellular uptake and accumulation of lipids, CD36 increased levels on monocytes could represent a proatherogenic condition in HIV-infected patients.

Adult↗

PubMed2005

A point mutation affecting an SP1 binding site in the promoter of the ferrochelatase gene impairs gene transcription and causes erythropoietic protoporphyria.

OBJECTIVE: Clinical manifestation of erythropoietic protoporphyria (EPP) results from coinheritance of a mutated allele and a wild-type low-expressed allele of the ferrochelatase (FECH) gene. Currently, up to 90 different mutations affecting the coding region or splicing junctions of the FECH gene have been identified. Despite the high molecular heterogeneity, no functional mutations have been previously reported in the promoter region. The weaker allele expression has been controversially associated to the presence of different intragenic polymorphisms. METHODS: We applied a two-step screening strategy using denaturing gradient gel electrophoresis followed by direct sequencing in order to rapidly identify FECH gene mutations in Italian EPP patients. We identified two unrelated subjects showing a normal FECH coding region but a single G>C base substitution at position -250 in the FECH promoter and the -251G, IVS1-23T, and IVS3-48C polymorphisms in trans to the substitution. To investigate the effect of the -250G>C mutation on protein binding to the FECH promoter, we conducted electro mobility shift assay (EMSA) and supershift analysis. To determine its effect on the transcriptional activity, K562 and Jurkat cell lines were transiently transfected. RESULTS: EMSA showed that the -250G>C mutation results in the loss of an SP1 binding site, and transient transfection assays demonstrated that such mutation strongly impairs promoter activity. Moreover, we showed that the -251A>G polymorphism, although unable to affect SP1 binding, displays a significant reduction in the transcriptional activity of the promoter. CONCLUSION: This is the first report of a mutation in the FECH promoter affecting binding of a transcription factor and causing EPP phenotype.

Base Sequence↗