Comparing viral metagenomics methods using a highly multiplexed human viral pathogens reagent.

Unbiased metagenomic sequencing holds significant potential as a diagnostic tool for the simultaneous detection of any previously genetically described viral nucleic acids in clinical samples. Viral genome sequences can also inform on likely phenotypes including drug susceptibility or neutralization serotypes. In this study, different variables of the laboratory methods often used to generate viral metagenomics libraries were compared for their abilities to detect multiple viruses and generate full genome coverage. A biological reagent consisting of 25 different human RNA and DNA viral pathogens was used to estimate the effect of filtration and nuclease digestion, DNA/RNA extraction methods, pre-amplification and the use of different library preparation kits on the detection of viral nucleic acids. Filtration and nuclease treatment led to slight decreases in the percentage of viral sequence reads and number of viruses detected. For nucleic acid extractions silica spin columns improved viral sequence recovery relative to magnetic beads and Trizol extraction. Pre-amplification using random RT-PCR while generating more viral sequence reads resulted in detection of fewer viruses, more overlapping sequences, and lower genome coverage. The ScriptSeq library preparation method retrieved more viruses and a greater fraction of their genomes than the TruSeq and Nextera methods. Viral metagenomics sequencing was able to simultaneously detect up to 22 different viruses in the biological reagent analyzed including all those detected by qPCR. Further optimization will be required for the detection of viruses in biologically more complex samples such as tissues, blood, or feces.

A role for TRPV1 in influencing the onset of cardiovascular disease in obesity.

Obesity induced by Western diets is associated with type 2 diabetes mellitus and cardiovascular diseases, although underlying mechanisms are unclear. We investigated a murine model of diet-induced obesity to determine the effect of transient potential receptor vanilloid 1 (TRPV1) deletion on hypertension and metabolic syndrome. Wild-type and TRPV1 knockout mice were fed normal or high-fat diet from 3 to 15 weeks. High-fat diet-fed mice from both genotypes became obese, with similar increases in body and adipose tissue weights. High-fat diet-fed TRPV1 knockout mice showed significantly improved handling of glucose compared with high-fat diet-fed wild-type mice. Hypertension, vascular hypertrophy, and altered nociception were observed in high-fat diet-fed wild-type but not high-fat diet-fed TRPV1 knockout mice. Wild-type, but not high-fat diet-fed TRPV1 knockout, mice demonstrated remodeling in terms of aortic vascular hypertrophy and increased heart and kidney weight, although resistance vessel responses were similar in each. Moreover, the wild-type mice had significantly increased plasma levels of leptin, interleukin 10 and interleukin 1ß, whereas samples from TRPV1 knockout mice did not show significant increases. Our results do not support the concept that TRPV1 plays a major role in influencing weight gain. However, we identified a role of TRPV1 in the deleterious effects observed with high-fat feeding in terms of inducing hypertension, impairing thermal nociception sensitivity, and reducing glucose tolerance. The observation of raised levels of adipokines in wild-type but not TRPV1 knockout mice is in keeping with TRPV1 involvement in stimulating the proinflammatory network that is central to obesity-induced hypertension and sensory neuronal dysfunction.

Involvement of human herpesvirus-6 variant B in classic Hodgkin's lymphoma via DR7 oncoprotein.

PURPOSE: Hodgkin's lymphoma (HL) is associated with the presence of EBV in Reed-Sternberg (RS) cells in ∼40% of cases. Here, we studied the presence of human herpesvirus type 6 (HHV-6) variant B in RS cells of HL patients and correlated results with clinical parameters. We then examined the implication of HHV-6 DR7B protein in cell deregulation. EXPERIMENTAL DESIGN: HHV-6 DR7B protein was produced in a Semliki Forest virus system. Polyclonal antibodies were then generated and used for immunochemical HHV-6 localization in HL biopsies. Binding between DR7B and p53 was studied using a double-hybrid system. Transactivation of NFκB was observed after transient transfection using reporter gene assays. We looked for Id2 factor expression after stable transfection of the BJAB cell line by reverse transcription-PCR and Western blot analysis. RESULTS: HHV-6 was more common in nodular sclerosis subtype HL, and DR7B oncoprotein was detected in RS cells for 73.7% of EBV-negative patients. Colocalization of EBV and HHV-6 was observed in RS cells of doubly infected patients. DR7B protein bound to human p53 protein. p105-p50/p65 mRNA expression and activation of the NFκB complex were increased when DR7B was expressed. Stable expression of DR7B exhibited a strong and uniform expression of Id2. A slightly higher percentage of remission was observed in patients with RS cells testing positive for DR7B than in those testing negative. CONCLUSIONS: Collectively, these data provide evidence for the implication of a novel agent, HHV-6, in cases of nodular sclerosis HL.

T-cadherin expression in cardiac allograft vasculopathy: bench to bedside translational investigation.

BACKGROUND: Coronary allograft vasculopathy (CAV) is the major limiting factor for long term survival after heart transplantation. The aim of this study was to identify gene candidates implicated in human CAV using a rat aortic allograft model in tandem with microarrays and quantitative real time PCR (Q-PCR). METHODS: Rat abdominal aortas were isografted (5) or allografted (5) from Brown-Norway to Lewis rats and grafts were harvested after day 8, 25 and 60. Agilent microarrays were then used to highlight differentially expressed genes between isografted and allografted rat aortas. Further investigation of a selected candidate gene was performed on human coronary arteries. RESULTS: 1829, 2582 and 1925 genes (fold changes >2 or <2 and p values <0.05) were differentially expressed at day 8, 25 and 60 respectively between isografs and allografts. Seventeen candidate genes were selected according to significant differential expression at day 60. These rat candidate genes were then validated by quantitative real time polymerase chain reaction (Q-PCR). One of these candidate genes, T-Cadherin (T-Cad) was further investigated, using immunohistochemistry (IHC), in human coronary arteries showing CAV compared to classical atherosclerosis present in ischemic cardiomyopathy (ICM) and normal coronary arteries present in dilated cardiomyopathy (DCM). Results showed an over expression of T-Cad in CAV and classical atherosclerosis compared to normal coronary arteries. CONCLUSIONS: T-Cad was found to be over expressed in CAV. T-Cad could potentially act as a trigger for smooth muscle cells (SMCs) proliferation and vascular remodelling observed in CAV leading to a diffuse narrowing of the arterial lumen.

Investigation of low-dose ritonavir on human peripheral blood mononuclear cells using gene expression whole genome microarrays.

Ritonavir is a protease inhibitor associated with metabolic abnormalities and cardiovascular disease. We have investigated the effects of low-dose ritonavir treatment on gene expression in peripheral blood mononuclear cells (PBMC) of 10 healthy donors. Results using whole genome Illumina microarrays show that ritonavir modulates a number of genes implicated in lipid metabolism, inflammation and atherosclerosis. These candidate genes are dual specificity phosphatase 1 DUSP1), Kelch domain containing 3 (KLHDC3), neutral cholesterol ester hydrolase 1 (NCEH1) and acyl-CoA synthetase short-chain family member 2 (ACSS2). Validation experiments using quantitative PCR showed that ritonavir (at 100 mg once daily and 100 mg twice daily significantly down-regulated these 4 selected candidate genes in 20 healthy individuals. Lower expression levels of these 4 candidate genes, known to play a critical role in inflammation, lipid metabolism and atherosclerosis, may explain ritonavir adverse effects in patients.

Prevention of atherosclerosis in patients living with HIV.

INVESTIGATIONAL PRODUCT: Rosuvastatin (Crestor; Astra Zeneca). ACTIVE INGREDIENTS: Rosuvastatin (5 mg). STUDY TITLE: Prevention of Atherosclerosis in Patients Living with HIV. PHASE OF STUDY: Phase III. AIMS: PRIMARY AIM: To assess whether rosuvastatin therapy could slow the progression of the carotid intima-media thickness (C-IMT; as measured by the change in the mean IMT of the near and far walls of the distal common carotid arteries) over 2 years in HIV-infected patients (HIV-IP). SECONDARY AIMS: To assess whether rosuvastatin therapy could reduce highly sensitive C reactive protein (hs-CRP) inflammatory marker that is increased in HIV-IP.To assess the effect of rosuvastatin therapy on serum lipid levels (total cholesterol [TC], low-density lipoprotein [LDL] cholesterol, high-density lipoprotein [HDL] cholesterol and triglycerides [TG]) and apolipoproteins (APO A1, APO B and APO B/A1).To assess the safety of rosuvastatin in HIV-IP through the evaluation of clinical laboratory analyses (liver function tests and creatine kinase) and adverse events (AEs). STUDY DESIGN: Two-year randomized, double-blind, placebo-controlled, parallel group study. PLANNED SAMPLE SIZE: 320 HIV-IP. SUMMARY OF ELIGIBILITY CRITERIA: HIV-IP who are aged between 30 and 60 years, with a CD4 count. greater than 200 cells/mm(3). Patients must be stable on combination antiretroviral therapy (cART) for at least 12 months and have a 10-year CVD risk of less than 20% (using the Framingham risk score). NUMBER OF STUDY CENTERS: One. DURATION OF TREATMENT: Two years (5 mg rosuvastatin or placebo once daily). DOSE AND ROUTE OF ADMINISTRATION: Oral rosuvastatin (5 mg) once daily. The incidence of cardiovascular disease (CVD) in HIV-IP is at least three times higher than in the general population and further increases each year with combination anti-retroviral therapy (cART). The carotid atherosclerosis progression rate is 10 times higher in HIV-IP than in uninfected individuals. The aim of this study is to assess whether therapy with 5 mg rosuvastatin could: 1) Slow the progression in the mean IMT of the distal common carotid arteries over two years in HIV-IP.2) Change the concentration in the inflammatory marker--hs-CRP, which is increased in HIV-IP.3) Change the concentrations of TC, LDL cholesterol, HDL cholesterol, TG, apolipoproteins (APO) B, APO A1 and APO B/A1.4) Be administered safely in the study population. Pharmacological intervention with rosuvastatin will be evaluated in a double-blind, placebo-controlled, randomized clinical trial in HIV-IP treated with cART not matching the published selection criteria for lipid-lowering therapy. For the first time, this study will investigate anti-inflammatory and anti-atherogenic effects of a pharmacological lipid-lowering agent in HIV-IP that may lead to the reduction of CVD.

CD36 is significantly correlated with adipophilin in human carotid lesions and inversely correlated with plasma ApoAI.

OxLDL uptake and cholesterol efflux inhibition in macrophages play a key role in atherosclerotic plaque formation, rupture, and thrombotic ischemia. This study investigates genes implicated in OxLDL uptake (CD36, SRA), cholesterol efflux inhibition (adipophilin, ADFP), and inflammatory recruitments of leukocytes (IL-8) in plaque lesion areas (PLAs) compared to nonplaque lesion areas (NPLAs) in human carotid endarterectomy specimens. Gene and protein expressions were assayed using quantitative PCR and quantitative immunohistochemistry. Pearson tests were used to investigate potential correlation between (a) different gene expressions and (b) gene expression and patient's plasma constituents. CD36, SRA, ADFP, and IL-8 were shown to be significantly more expressed in PLA compared to NPLA. In PLA, a significant correlation was observed between CD36, SRA, ADFP, and IL-8 mRNA levels. Moreover, CD36 expression level was significantly inversely correlated to plasma marker ApoAI. The above investigated genes/proteins may play a key role in the maturation of atherosclerotic lesions.

CD36 N-terminal cytoplasmic domain is not required for the internalization of oxidized low-density lipoprotein.

The uptake of OxLDLs (oxidized low density lipoproteins) by CD36-expressing macrophages in the arterial intima and the subsequent 'foam cell' formation represents a crucial step in the initiation and development of atherosclerotic plaques. The present study has addressed the function of the CD36 N-terminal cytoplasmic domain in the binding and internalization of OxLDL. A selection of CD36 N-terminal cytoplasmic domain mutants were generated and stably expressed in HEK-293 (human embryonic kidney) cells. The capacity of three mutants [CD36_C3/7-A (CD36-C3A/C7A), CD36_D4/R5-A (CD36-D4A/R5A) and CD36_nCPD(-) (CD36 lacking the N-terminal cytoplasmic domain)] to bind and endocytose OxLDL was then studied using immunofluorescence microscopy and quantitative fluorimetry. Each of the CD36 constructs was expressed at differing levels at the cell surface, as measured by flow cytometry and Western blotting. Following incubation with DiI (1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate)-OxLDL, cells bearing the CD36_wt (wild-type CD36), CD36_C3/7-A, CD36_D4/R5-A and CD36_nCPD(-) constructs all internalized DiI-OxLDL into endosomal structures, whereas empty-vector-transfected cells failed to do so, indicating that, unlike the C-terminal cytoplasmic domain, the N-terminal cytoplasmic domain is not essential for the endocytosis of OxLDL. In conclusion, the uptake of OxLDL by CD36 is not reliant on the presence of the CD36 N-terminal cytoplasmic domain. However, the N-terminal cytoplasmic domain may conceivably be implicated in the maturation of CD36.

CD36 and macrophages in atherosclerosis.

CD36 is a multi-ligand scavenger receptor present on the surface of a number of cells such as platelets, monocytes/macrophages, endothelial and smooth muscle cells. Monocyte/macrophage CD36 has been shown to play a critical role in the development of atherosclerotic lesions by its capacity to bind and endocytose oxidized low density lipoproteins (OxLDL), and it is implicated in the formation of foam cells. However, the significance of CD36 in atherosclerosis has recently been called into question by different studies, and therefore its exact role still needs to be clarified. The aim of this article is to carefully review the importance of CD36 as an essential component in the pathogenesis of atherosclerosis.

Statin therapy-evidence beyond lipid lowering contributing to plaque stability.

Primarily statin drugs inhibit hepatic 3-hydroxy 3-methylglutaryl coenzyme A (HMG-CoA) reductase, which is responsible for the reduction in circulating low-density lipoprotein (LDL) cholesterol. Several findings from recent research studies indicate that statins have multiple actions that favorably influence key factors involved in the atherogenic process. These so-called pleiotropic properties affect various aspects of cell function, inflammation, coagulation, and vasomotor activity. These effects are mediated either indirectly through LDL cholesterol reduction or via a direct effect on cellular functions. Such actions may contribute to the early cardiovascular benefit observed in several outcome trials with statin drugs therapy. Although many of the pleiotropic properties of statins may be a class effect, some may be unique to certain agents and account for differences in their pharmacological activity. This review summarise the results of the major outcome trials of statins and non-statins therapy and the possible mechanisms beyond lipid lowering contributing to plaque stability.