Reduced serum hepcidin levels in patients with chronic hepatitis C

BACKGROUND/AIMS

Patients with chronic hepatitis C (CHC) often have increased liver iron, a condition associated with reduced sustained response to antiviral therapy, more rapid progression to cirrhosis, and development of hepatocellular carcinoma. The hepatic hormone hepcidin is the major regulator of iron metabolism and inhibits iron absorption and recycling from erythrophagocytosis. Hepcidin decrease is a possible pathophysiological mechanism of iron overload in CHC, but studies in humans have been hampered so far by the lack of reliable quantitative assays for the 25-amino acid bioactive peptide in serum (s-hepcidin).

METHODS

Using a recently validated immunoassay, we measured s-hepcidin levels in 81 untreated CHC patients and 57 controls with rigorous definition of normal iron status. All CHC patients underwent liver biopsy with histological iron score.

RESULTS

s-hepcidin was significantly lower in CHC patients than in controls (geometric means with 95% confidence intervals: 33.7, 21.5-52.9 versus 90.9, 76.1-108.4 ng/mL, respectively; p<0.001). In CHC patients, s-hepcidin significantly correlated with serum ferritin and histological total iron score, but not with s-interleukin-6. After stratification for ferritin quartiles, s-hepcidin increased significantly across quartiles in both controls and CHC patients (chi for trend, p<0.001). However, in CHC patients, s-hepcidin was significantly lower than in controls for each corresponding quartile (analysis of variance, p<0.001).

CONCLUSIONS

These results, together with very recent studies in animal and cellular models, indicate that although hepcidin regulation by iron stores is maintained in CHC, the suppression of this hormone by hepatitis C virus is likely an important factor in liver iron accumulation in this condition.

Clinical Importance of Eosinophil Count in Nasal Fluid in Patients with Allergic and Non-Allergic Rhinitis

Eosinophil count in nasal fluid (ECNF) was used to differentiate nasal pathologies. Receiver Operating Characteristic (ROC) curve analysis and the area under the curve (AUC) were performed to evaluate the ECNF's accuracy in distinguishing allergic rhinitis (AR) from non-allergic rhinitis (NAR). We also evaluated the accuracy of ECNF in recognizing patients with mild and severe symptoms of rhinitis and patients with ineffective and effective clinical responses to antihistamines. 1,170 consecutive adult patients with a clinical history of rhinitis were studied. ECNF's median in AR was 6.0 and 2.0 in NAR and the best cut-off value was > 3.0, AUC = 0.75. ECNF's median in AR with mild nasal symptoms was 3.0 and 7.0 with severe symptoms, and the best cut-off value was 4.0, AUC = 0.90. ECNF's median in NAR with mild nasal symptoms was 2.0 and 8.5 with severe symptoms, and the best cut-off value was > 4.0, AUC = 0.86. ECNF's median in AR with effective clinical response to antihistamines was 4.0 and 8.0 with ineffective response, the best cut-off value was ≤ 5.0, AUC = 0.94. ECNF's median in NAR with an effective clinical response to antihistamines was 1.0 and 2.0 with ineffective response, and the best cut-off value was ≤ 3.0, AUC = 0.64. Our results suggest an interesting practical use of ECNF data as evaluator of the clinical severity both AR and NAR. As predictor of the clinical response to antihistamines, ECNF is accurate only in patients with AR. The ECNF's performance was moderately accurate in distinguish patients with AR and NAR.

Endothelin‐1 serum levels correlate with MCP‐1 but not with homocysteine plasma concentration in patients with systemic sclerosis

OBJECTIVES

To determine whether homocysteine (Hcy) plasma levels are correlated with molecules indicative of endothelial cell and fibroblast activation, including endothelin-1 (ET-1) and monocyte chemoattractant protein-1 and -3 (MCP-1, MCP-3), in patients with systemic sclerosis (SSc).

METHODS

Eighty-two patients were enrolled in this study; the control group included 75 age- and sex-matched subjects. Plasma Hcy was determined by high-performance liquid chromatography; folic acid, and vitamin B(12) plasma levels were determined by a chemiluminescence method. ET-1, MCP-1, and MCP-3 were determined by enzyme-linked immunosorbent assay (ELISA). Analysis of the 677C-->T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene was performed by polymerase chain reaction (PCR) and digestion with the enzyme HinfI.

RESULTS

Hcy levels were lower in patients whereas ET-1 was significantly higher in patients and correlated with MCP-1. Stratification of the patients on the basis of Hcy levels was not associated with any statistical difference in the concentration of ET-1, MCP-1, and MCP-3. Patients with diffuse disease presented the highest levels of ET-1 and MCP-1. The distribution of the MTHFR genotypes was not different in patients and controls.

CONCLUSIONS

In SSc, Hcy plasma concentration does not influence ET-1, MCP-1, or MCP-3 levels. On the contrary, ET-1, a marker of vascular activation, correlates with MCP-1, a chemokine involved in the fibrotic process of SSc.

Human parvovirus B19 infection and autoimmunity

Human parvovirus B19 infection is responsible for a wide range of human diseases ranging from mild erythema infectiosum in immunocompetent children to fetal loss in primary infected pregnant women and aplastic anemia or lethal cytopenias in adult immunocompromised patients. Since persistent viral infection is responsible for an autoimmune response and clinical symptoms can mimic autoimmune inflammatory disorders, parvovirus B19 is the object of intense efforts to clarify whether it is also able to trigger autoimmune diseases. Indeed the virus has been implicated as the causative or the precipitating agent of several autoimmune disorders including rheumatoid arthritis, systemic lupus, antiphospholipid syndrome, systemic sclerosis and vasculitides. Molecular mimicry between host and viral proteins seems to be the main mechanism involved in the induction of autoimmunity. By means of a random peptide library approach, we have identified a peptide that shares homology with parvovirus VP1 protein and with human cytokeratin. Moreover the VP peptide shares similarity with the transcription factor GATA1 that plays an essential role in megakaryopoiesis and in erythropoiesis. These new data sustain the role played by molecular mimicry in the induction of cross-reactive (auto)antibodies by parvovirus B19 infection.

Novel serum paraoxonase activity assays are associated with coronary artery disease

BACKGROUND

Serum paraoxonase (PON1) exerts antiatherogenic effects. Novel PON1 enzymatic tests have been recently developed: 5-thiobutyl butyrolactone (TBBL) estimates PON1 lactonase activity, whereas 7-O-diethylphosphoryl-3-cyano-4-methyl-7-hydroxycoumarin (DEPCyMC) is considered a surrogate marker of PON1 concentration. The TBBL to DEPCyMC ratio provides the normalized lactonase activity (NLA), which may reflect the degree of PON1 lactonase catalytic stimulation. The aim of this study was to evaluate for the first time TBBLase and DEPCyMCase activity in patients with coronary artery disease (CAD).

METHODS

An angiography-based case-control study was conducted, including 300 sex- and age-matched subjects [100 CAD-free, 100 CAD without myocardial infarction (MI) and 100 CAD with MI].

RESULTS

A low DEPCyMCase activity (lowest vs. highest tertile: OR 2.96, 95% CI 1.18-7.43) and a high NLA (highest vs. lowest tertile: OR 3.25, 95% CI 1.28-8.26) were both associated with CAD, independent of classical atherosclerosis risk factors, lipid-lowering therapy and PON1 genotype. Total TBBLase activity was, however, not different in CAD compared to CAD-free subjects.

CONCLUSIONS

Novel PON1 activity assays may be associated with CAD. In this study, CAD patients had low DEPCyMCase activity, a possible marker of low PON1 concentration, but showed a high stimulation of PON1 lactonase activity.

Additive effect of LRP8/APOER2 R952Q variant to APOE epsilon2/epsilon3/epsilon4 genotype in modulating apolipoprotein E concentration and the risk of myocardial infarction: a case-control study

BACKGROUND

The R952Q variant in the low density lipoprotein receptor-related protein 8 (LRP8)/apolipoprotein E receptor 2 (ApoER2) gene has been recently associated with familial and premature myocardial infarction (MI) by means of genome-wide linkage scan/association studies. We were interested in the possible interaction of the R952Q variant with another established cardiovascular genetic risk factor belonging to the same pathway, namely apolipoprotein E (APOE) epsilon2/epsilon3/epsilon4 genotype, in modulating apolipoprotein E (ApoE) plasma levels and risk of MI.

METHODS

In the Italian cohort used to confirm the association of the R952Q variant with MI, we assessed lipid profile, apolipoprotein concentrations, and APOE epsilon2/epsilon3/epsilon4 genotype. Complete data were available for a total of 681 subjects in a case-control setting (287 controls and 394 patients with MI).

RESULTS

Plasma ApoE levels decreased progressively across R952Q genotypes (mean levels +/- SD = RR: 0.045 +/- 0.020, RQ: 0.044 +/- 0.014, QQ: 0.040 +/- 0.008 g/l; P for trend = 0.047). Combination with APOE genotypes revealed an additive effect on ApoE levels, with the highest level observed in RR/non-carriers of the E4 allele (0.046 +/- 0.021 g/l), and the lowest level in QQ/E4 carriers (0.035 +/- 0.009 g/l; P for trend = 0.010). QQ/E4 was also the combined genotype with the most significant association with MI (OR 3.88 with 95%CI 1.08-13.9 as compared with RR/non-carriers E4).

CONCLUSION

Our data suggest that LRP8 R952Q variant may have an additive effect to APOE epsilon2/epsilon3/epsilon4 genotype in determining ApoE concentrations and risk of MI in an Italian population.

Genome-wide association of early-onset myocardial infarction with single nucleotide polymorphisms and copy number variants

We conducted a genome-wide association study testing single nucleotide polymorphisms (SNPs) and copy number variants (CNVs) for association with early-onset myocardial infarction in 2,967 cases and 3,075 controls. We carried out replication in an independent sample with an effective sample size of up to 19,492. SNPs at nine loci reached genome-wide significance: three are newly identified (21q22 near MRPS6-SLC5A3-KCNE2, 6p24 in PHACTR1 and 2q33 in WDR12) and six replicated prior observations (9p21, 1p13 near CELSR2-PSRC1-SORT1, 10q11 near CXCL12, 1q41 in MIA3, 19p13 near LDLR and 1p32 near PCSK9). We tested 554 common copy number polymorphisms (>1% allele frequency) and none met the pre-specified threshold for replication (P < 10(-3)). We identified 8,065 rare CNVs but did not detect a greater CNV burden in cases compared to controls, in genes compared to the genome as a whole, or at any individual locus. SNPs at nine loci were reproducibly associated with myocardial infarction, but tests of common and rare CNVs failed to identify additional associations with myocardial infarction risk.

High resolution preparation of monocyte-derived macrophages (MDM) protein fractions for clinical proteomics

BACKGROUND

Macrophages are involved in a number of key physiological processes and complex responses such as inflammatory, immunological, infectious diseases and iron homeostasis. These cells are specialised for iron storage and recycling from senescent erythrocytes so they play a central role in the fine tuning of iron balancing and distribution. The comprehension of the many physiological responses of macrophages implies the study of the related molecular events. To this regard, proteomic analysis, is one of the most powerful tools for the elucidation of the molecular mechanisms, in terms of changes in protein expression levels.

RESULTS

Our aim was to optimize a protocol for protein fractionation and high resolution mapping using human macrophages for clinical studies. We exploited a fractionation protocol based on the neutral detergent Triton X-114. The 2D maps of the fractions obtained showed high resolution and a good level of purity. Western immunoblotting and mass spectrometry (MS/MS analysis) indicated no fraction cross contamination. On 2D-PAGE mini gels (7 x 8 cm) we could count more than five hundred protein spots, substantially increasing the resolution and the number of detectable proteins for the macrophage proteome. The fractions were also evaluated, with preliminary experiments, using Surface Enhanced Laser Desorption Ionization Time of Flight Mass Spectrometry (SELDI-TOF-MS).

CONCLUSION

This relatively simple method allows deep investigation into macrophages proteomics producing discrete and accurate protein fractions, especially membrane-associated and integral proteins. The adapted protocol seems highly suitable for further studies of clinical proteomics, especially for the elucidation of the molecular mechanisms controlling iron homeostasis in normal and disease conditions.

Antiflagellin antibodies recognize the autoantigens Toll-Like Receptor 5 and Pals 1-associated tight junction protein and induce monocytes activation and increased intestinal permeability in Crohn's disease

BACKGROUND AND OBJECTIVES

Bacterial flagellin is considered an important antigen in Crohn's disease (CD) as it activates innate immunity through Toll-Like Receptor 5 (TLR5) engagement and induces an elevated adaptive immune response. Little is known about the presence of an autoimmune process in CD. We aimed to identify pathogenically relevant autoantigen targets in CD.

METHODS

We screened a random peptide library with pooled sera of patients with active CD. Transepithelial flux of [3H] mannitol in T84 human intestinal epithelial cell line was used to study the epithelial barrier function. Monocyte activation was evaluated by surface expression of activation markers and by production of pro-inflammatory cytokines. Gene modulation of T84 cells exposed to antipeptide antibodies was analysed by gene array.

RESULTS

We identified a peptide that shares homology with Salmonella typhimurium flagellin and with self-antigens such as TLR5 and cell junction protein, Pals 1-associated tight junction protein. The affinity-purified antipeptide antibodies recognized the self-antigens and induced increased intestinal epithelial cell permeability. Moreover, the antibodies induced monocyte activation upon binding TLR5. Finally, in cultured intestinal cells (T84) the purified antibodies induced the modulation of clusters of proinflammatory genes similar to the one induced by the engagement of TLR5 by its natural ligand flagellin.

CONCLUSIONS

Antibodies directed against an immunodominant peptide of flagellin recognize self-antigens and are functionally active suggesting the presence of an autoimmune process that can both facilitate loss of tolerance to intestinal microflora by increasing cell permeability and amplify the innate immunity involvement through a novel mechanism of TLR5 activation.

Clinical, pathological, and molecular correlates in ferroportin disease: a study of two novel mutations

BACKGROUND/AIMS

Clinico-pathological manifestations of ferroportin (Fpn) disease (FD) are heterogeneous, with some patients presenting with iron overload predominantly in macrophages ("M" phenotype), others predominantly in hepatocytes ("H" phenotype). This appears to reflect functional heterogeneity of Fpn mutants, with loss-of-function generally resulting in the M type.

METHODS

Two unrelated probands with "non-HFE" hemochromatosis were screened for Fpn mutations. Mutants were functionally characterized by immunofluorescence microscopy, evaluation of their ability to bind hepcidin and export iron, and by expressing them in zebrafish.

RESULTS

Two novel Fpn mutations were identified: I152F in patient-1, presenting with typical M phenotype; and L233P in patient-2, presenting with ambiguous features (massive overload in both macrophages and hepatocytes). Molecular studies suggested loss of function in both cases. The I152F, normally localized on cell membrane and internalized by hepcidin, showed a unique "primary" deficit of iron export capability. The L233P did not appropriately traffic to cell surface. Loss of function was confirmed by expressing both mutants in vivo in zebrafish, resulting in iron limited erythropoiesis. Clinical manifestations were likely enhanced in both patients by non-genetic factors (HCV, alcohol).

CONCLUSIONS

The combination of careful review of clinico-pathological data with molecular studies can yield compelling explanations for phenotype heterogeneity in FD.

FADS genotypes and desaturase activity estimated by the ratio of arachidonic acid to linoleic acid are associated with inflammation and coronary artery disease

BACKGROUND

The delta-5 and delta-6 desaturases, encoded by FADS1 and FADS2 genes, are key enzymes in polyunsaturated fatty acid (PUFA) metabolism that catalyze the conversion of linoleic acid (LA) into arachidonic acid (AA) and that of alpha-linolenic acid (ALA) into eicosapentaenoic acid (EPA). Single-nucleotide polymorphisms (SNPs) in FADS1 and FADS2 have been associated with different concentrations of AA and LA, and those associations have possible functional consequences for desaturase activity.

OBJECTIVE

We aimed to evaluate the possible association among FADS genotypes, desaturase activity, inflammation, and coronary artery disease (CAD).

DESIGN

Thirteen FADS SNPs and the ratio of AA to LA (AA/LA) on red blood cell (RBC) membranes, a marker of desaturase activity, were evaluated in 876 subjects with (n = 610) or without (n = 266) angiographically documented CAD.

RESULTS

Both AA/LA and the ratio of EPA to ALA (EPA/ALA) were higher in patients with CAD than in those without CAD, but, in a multiple logistic regression model, only a higher AA/LA resulted an independent risk factor for CAD (odds ratio: 2.55; 95% CI: 1.61, 4.05 for higher compared with lower ratio tertile; P for trend < 0.001). Furthermore, concentrations of high-sensitivity C-reactive protein increased progressively across tertiles of AA/LA. Graded increases in high-sensitivity C-reactive protein concentrations and CAD risk were related to the carriership of FADS haplotypes, including the alleles associated with a higher ratio.

CONCLUSION

In populations following a Western diet, subjects carrying FADS haplotypes that are associated with higher desaturase activity may be prone to a proinflammatory response favoring atherosclerotic vascular damage.

Epigenetic control of 11 beta-hydroxysteroid dehydrogenase 2 gene promoter is related to human hypertension

BACKGROUND

Lower activity of 11 beta-hydroxysteroid dehydrogenase 2 (11beta-HSD2) classically induces hypertension by leading to an altered tetrahydrocortisol- versus tetrahydrocortisone-metabolites (THFs/THE) shuttle. Recent cell culture and animal studies suggest a role for promoter methylation, a major epigenetic feature of DNA, in regulation of HSD11B2 expression. Little is known, however, of human HSD11B2 epigenetic control and its relationship with the onset of hypertension.

OBJECTIVE

To explore the possible relevance of HSD11B2 promoter methylation, by examining human peripheral blood mononuclear cell (PBMC) DNA and urinary THFs/THE ratio as a biochemical indicator of 11beta-HSD2 activity, in blood pressure control.

METHODS

Twenty-five essential hypertensives and 32 subjects on prednisone therapy were analyzed, the latter to investigate 11beta-HSD2 function in the development of hypertension.

RESULTS

Elevated HSD11B2 promoter methylation was associated with hypertension developing in glucocorticoid-treated patients in parallel with a higher urinary THFs/THE ratio. Essential hypertensives with elevated urinary THFs/THE ratio also showed higher HSD11B2 promoter methylation.

CONCLUSIONS

These results show a clear link between the epigenetic regulation through repression of HSD11B2 in PBMC DNA and hypertension.

Combined effect of hemostatic gene polymorphisms and the risk of myocardial infarction in patients with advanced coronary atherosclerosis

Background

Relative little attention has been devoted until now to the combined effects of gene polymorphisms of the hemostatic pathway as risk factors for Myocardial Infarction (MI), the main thrombotic complication of Coronary Artery Disease (CAD). The aim of this study was to evaluate the combined effect of ten common prothrombotic polymorphisms as a determinant of MI.

Methodology/Principal Findings

We studied a total of 804 subjects, 489 of whom with angiographically proven severe CAD, with or without MI (n = 307; n = 182; respectively). An additive model considering ten common polymorphisms [Prothrombin 20210G>A, PAI-1 4G/5G, Fibrinogen β -455G>A, FV Leiden and “R2”, FVII -402G>A and -323 del/ins, Platelet ADP Receptor P2Y12 -744T>C, Platelet Glycoproteins Ia (873G>A), and IIIa (1565T>C)] was tested. The prevalence of MI increased linearly with an increasing number of unfavorable alleles (χ² for trend = 10.68; P = 0.001). In a multiple logistic regression model, the number of unfavorable alleles remained significantly associated with MI after adjustment for classical risk factors. As compared to subjects with 3-7 alleles, those with few (≤2) alleles had a decreased MI risk (OR 0.34, 95%CIs 0.13–0.93), while those with more (≥8) alleles had an increased MI risk (OR 2.49, 95%CIs 1.03–6.01). The number of procoagulant alleles correlated directly (r = 0.49, P = 0.006) with endogenous thrombin potential.

Conclusions

The combination of prothrombotic polymorphisms may help to predict MI in patients with advanced CAD.

An LRP8 variant is associated with familial and premature coronary artery disease and myocardial infarction

Our previous genomewide linkage scan of 428 nuclear families (GeneQuest) identified a significant genetic susceptibility locus for premature myocardial infarction (MI) on chromosome 1p34-36. We analyzed candidate genes in the locus with a population-based association study involving probands with premature coronary artery disease (CAD) and/or MI from the GeneQuest families (381 cases) and 560 controls without stenosis detectable by coronary angiography. A nonconservative substitution, R952Q, in LRP8 was significantly associated with susceptibility to premature CAD and/or MI by use of both population-based and family-based designs. Three additional white populations were used for follow-up replication studies: another independent cohort of CAD- and/or MI-affected families (GeneQuest II: 441 individuals from 22 pedigrees), an Italian cohort with familial MI (248 cases) and 308 Italian controls, and a separate Cleveland GeneBank cohort with sporadic MI (1,231 cases) and 560 controls. The association was significantly replicated in two independent populations with a family history of CAD and/or MI, the GeneQuest II family-based replication cohort and the Italian cohort, but not in the population with sporadic disease. The R952Q variant of LRP8 increased activation of p38 mitogen-activated protein kinase by oxidized low-density lipoprotein. This extensive study, involving multiple independent populations, provides the first evidence that genetic variants in LRP8 may contribute to the development of premature and familial CAD and MI.

Gene sequence variations of the platelet P2Y12 receptor are associated with coronary artery disease

BACKGROUND

The platelet P2Y12 receptor plays a key role in platelet activation. The H2 haplotype of the P2Y12 receptor gene (P2RY12) has been found to be associated with maximal aggregation response to adenosine diphosphate (ADP) and with increased risk for peripheral arterial disease. No data are available on its association with coronary artery disease (CAD).

METHODS

The H2 haplotype of the P2RY12 was determined in 1378 unrelated patients of both sexes selected according to the presence of significant coronary artery disease (CAD group) or having normal coronary angiogram at cardiac catheterization (CAD-free group). Significant coronary artery disease was angiographically determined, and was defined as a greater than 50% visually estimated luminal diameter stenosis in at least one major epicardial coronary artery.

RESULTS

In the studied population 71.9% had CAD (n = 991) and 28.1% had normal coronary angiogram (n = 387). H2 haplotype carriers were more frequent in the CAD group (p = 0.03, OR = 1.36, 95%CI = 1.02-1.82). The H2 haplotype was significantly associated with CAD in non-smokers (p = 0.007, OR = 1.83 95%CI = 1.17-2.87), but not in smokers. The association remained significant after adjustment for other covariates (age, triglycerides, HDL, hypertension, diabetes) by multivariate logistic regression (p = 0.004, OR = 2.32 95%CI = 1.30-4.15).

CONCLUSION

Gene sequence variations of the P2Y12 receptor gene are associated with the presence of significant CAD, particularly in non-smoking individuals.

Acute Hemolytic Anemia With Acanthocytosis Associated With High-Dose Misoprostol for Medical Abortion

We report a case of acute hemolytic anemia in a 21-year-old Nigerian woman after high-dose misoprostol (4 mg), used for medical abortion. The major causes of inherited or immune hemolytic anemia were excluded. The patient's peripheral blood smear showed acanthocytes and anisopoikilocytosis, which progressively disappeared in the days postingestion. We evaluated RBC features, and we observed reduced RBC Na+ and K+ content and abnormalities in membrane cation transport pathways and in Ca2+ activated K+ channel (Gardos channel), suggesting possible direct effects of misoprostol on RBCs. Although further studies need to be carried out, the present case suggests that high-dose misoprostol, a prostaglandin E1 analogue, severely affects RBC features and causes an acquired acute hemolytic anemia, which is self-limited when misoprostol is withdrawn.

Endothelial cells' activation and apoptosis induced by a subset of antibodies against human cytomegalovirus: relevance to the pathogenesis of atherosclerosis

BACKGROUND

Human cytomegalovirus (hCMV) is involved in the pathogenesis of atherosclerosis. We have previously shown in patients with atherosclerosis that antibodies directed against the hCMV-derived proteins US28 and UL122 are able to induce endothelial cell damage and apoptosis of non-stressed endothelial cells through cross-rection with normally expressed surface molecules. Our aim was to dissect the molecular basis of such interaction and to investigate mechanisms linking innate immunity to atherosclerosis.

METHODOLOGY/PRINCIPAL FINDINGS

We analysed the gene expression profiles in endothelial cells stimulated with antibodies affinity-purified against either the UL122 or the US28 peptides using the microarray technology. Microarray results were validated by quantitative PCR and by detection of proteins in the medium. Supernatant of endothelial cells incubated with antibodies was analysed also for the presence of Heat Shock Protein (HSP)60 and was used to assess stimulation of Toll-Like Receptor-4 (TLR4). Antibodies against UL122 and US28 induced the expression of genes encoding for adhesion molecules, chemokines, growth factors and molecules involved in the apoptotis process together with other genes known to be involved in the initiation and progression of the atherosclerotic process. HSP60 was released in the medium of cells incubated with anti-US28 antibodies and was able to engage TLR4.

CONCLUSIONS/SIGNIFICANCE

Antibodies directed against hCMV modulate the expression of genes coding for molecules involved in activation and apoptosis of endothelial cells, processes known to play a pivotal role in the pathogenesis of atherosclerosis. Moreover, endothelial cells exposed to such antibodies express HSP60 on the cell surface and release HSP60 in the medium able to activate TLR4. These data confirm that antibodies directed against hCMV-derived proteins US28 and UL122 purified from patients with coronary artery disease induce endothelial cell damage and support the hypothesis that hCMV infection may play a crucial role in mediating the atherosclerotic process.

ALOX5AP gene variants and risk of coronary artery disease: an angiography-based study

The aim of this study was to explore the role of variants of the gene encoding arachidonate 5-lipoxygenase-activating protein (ALOX5AP) as possible susceptibility factors for coronary artery disease (CAD) and myocardial infarction (MI) in patients with or without angiographically proven CAD. A total of 1431 patients with or without angiographically documented CAD were examined simultaneously for seven ALOX5AP single-nucleotide polymorphisms, allowing reconstruction of the at-risk haplotypes (HapA and HapB) previously identified in the Icelandic and British populations. Using a haplotype-based approach, HapA was not associated with either CAD or MI. On the other hand, HapB and another haplotype within the same region (that we named HapC) were significantly more represented in CAD versus CAD-free patients, and these associations remained significant after adjustment for traditional cardiovascular risk factors by logistic regression (HapB: odds ratio (OR) 1.67, 95% confidence interval (CI) 1.04-2.67; P=0.032; HapC: OR 2.41, 95% CI 1.09-5.32; P=0.030). No difference in haplotype distributions was observed between CAD subjects with or without a previously documented MI. Our angiography-based study suggests a possible modest role of ALOX5AP in the development of the atheroma rather than in its late thrombotic complications such as MI.