Elisabetta Schiaroli

Efficacy of the CCR5 Antagonist Maraviroc in Reducing Early, Ritonavir-Induced Atherogenesis and Advanced Plaque Progression in Mice

Background— CCR5 plays an important role in atherosclerosis and ischemic cardiovascular diseases, as well as in HIV replication and diffusion. HIV infection is characterized by a high burden of cardiovascular diseases, particularly in subjects exposed to ritonavir-boosted protease inhibitors. Maraviroc, a CCR5 antagonist antiretroviral drug, might provide benefit for patients with M-tropic HIV infections at high risk for cardiovascular diseases. Methods and Results— Exposure to maraviroc limits the evolution and associated systemic inflammation of ritonavir-induced atherosclerotic in ApoE−/− mice and inhibits plaques development in a late model of atherosclerosis in which dyslipidemia plays the main pathogenic role. In ritonavir-treated mice, maraviroc reduced plaque areas and macrophage infiltration; downregulated the local expression of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-17A; and reduced tumor necrosis factor-&agr; and RANTES (regulated on activation, normal T cell expressed, and secreted). Moreover, maraviroc counterregulated ritonavir-induced lipoatrophy and interlelukin-6 gene expression in epididymal fat, along with the splenic proinflammatory profile and expression of CD36 on blood monocytes. In the late model, maraviroc inhibited atherosclerotic progression by reducing macrophage infiltration and lowering the expression of adhesion molecules and RANTES inside the plaques. However, limited systemic inflammation was observed. Conclusions— In a mouse model of genetic dyslipidemia, maraviroc reduced the atherosclerotic progression by interfering with inflammatory cell recruitment into plaques. Moreover, in mice characterized by a general ritonavir-induced inflammation, maraviroc reversed the proinflammatory profile. Therefore, maraviroc could benefit HIV-positive patients with residual chronic inflammation who are at a high risk of acute coronary disease despite a suppressive antiretroviral therapy. To determine these benefits, large clinical studies are needed.

Efficacy of CCR5 Antagonist Maraviroc in Reducing the Early, Ritonavir Induced, Atherogenesis and the Advanced Plaque Progression in Mice

Background— CCR5 plays an important role in atherosclerosis and ischemic cardiovascular diseases, as well as in HIV replication and diffusion. HIV infection is characterized by a high burden of cardiovascular diseases, particularly in subjects exposed to ritonavir-boosted protease inhibitors. Maraviroc, a CCR5 antagonist antiretroviral drug, might provide benefit for patients with M-tropic HIV infections at high risk for cardiovascular diseases. Methods and Results— Exposure to maraviroc limits the evolution and associated systemic inflammation of ritonavir-induced atherosclerotic in ApoE−/− mice and inhibits plaques development in a late model of atherosclerosis in which dyslipidemia plays the main pathogenic role. In ritonavir-treated mice, maraviroc reduced plaque areas and macrophage infiltration; downregulated the local expression of vascular cell adhesion molecule-1, intercellular adhesion molecule-1, monocyte chemoattractant protein-1, and interleukin-17A; and reduced tumor necrosis factor-&agr; and RANTES (regulated on activation, normal T cell expressed, and secreted). Moreover, maraviroc counterregulated ritonavir-induced lipoatrophy and interlelukin-6 gene expression in epididymal fat, along with the splenic proinflammatory profile and expression of CD36 on blood monocytes. In the late model, maraviroc inhibited atherosclerotic progression by reducing macrophage infiltration and lowering the expression of adhesion molecules and RANTES inside the plaques. However, limited systemic inflammation was observed. Conclusions— In a mouse model of genetic dyslipidemia, maraviroc reduced the atherosclerotic progression by interfering with inflammatory cell recruitment into plaques. Moreover, in mice characterized by a general ritonavir-induced inflammation, maraviroc reversed the proinflammatory profile. Therefore, maraviroc could benefit HIV-positive patients with residual chronic inflammation who are at a high risk of acute coronary disease despite a suppressive antiretroviral therapy. To determine these benefits, large clinical studies are needed.

Management of Hepatitis B Virus Reactivation in Patients with Hematological Malignancies Treated with Chemotherapy

Introduction:Hepatitis B virus (HBV) reactivation is a majorcause of morbidity and mortality in patients with hematologicalmalignancies who receive cytotoxic chemotherapy. Wehave therefore carried out a prospective observational studyout to assess the incidence, prevalence, and clinical course ina cohort of these patients.Methods:HBV and HCV markers and liver function indiceswere monitored prospectively in 318 consecutive patients(171 males, 147 females; mean age 57 years) with hematologicalmalignancies, who had been referred to the HematologyDivision, Perugia University, between October 2005and March 2007 and followed up for at least 6 months.Results:At diagnosis, 32 patients (10%) had received HBVvaccination; 30 were responders. At least one HBV marker waspositive in 70/318 patients (22%): 14 (20%) were HBsAg-positive(HBV surface antigen-positive), 13 (19%) were only anti-HBc positive (antibodies to HB core antigen), and 43(61%)were anti-HBc and anti-HBs positive. Twelve HBsAg+ patientsreceived nucleoside/nucleotide analogs (adefovir [six patients],lamivudine [four], and combined adefovir/lamivudine[two non-responders to lamivudine]). After 6 months oftherapy, HBV-DNA was negative and transaminases were normalin nine of these 12 patients (adefovir [six], lamivudina[two], adefovir + lamivudina [one]). Seroreversion wasachieved in 3/13 patients (23%) who were only anti-HBc positive;all were on rituximab therapy and received adefovir.Seroreversion was not observed in any of the 43 patients whowere anti-HBc- and anti-HBs positive.Conclusions:Essential to the management of patients withhematological malignancies undergoing chemotherapy aresurveillance and prophylaxis of HBV infection together withprompt administration of nucleoside/nucleotide analogs incases of reactivation and/or seroreversion.

The HIV Matrix Protein p17 subverts Nuclear Receptors Expression and induces a STAT1-Dependent Proinflammatory Phenotype in Monocytes

Background Long-term remission of HIV-1 disease can be readily achieved by combinations of highly effective antiretroviral therapy (HAART). However, a residual persistent immune activation caused by circulating non infectious particles or viral proteins is observed under HAART and might contribute to an higher risk of non-AIDS pathologies and death in HIV infected persons. A sustained immune activation supports lipid dysmetabolism and increased risk for development of accelerated atehrosclerosis and ischemic complication in virologically suppressed HIV-infected persons receiving HAART. Aim While several HIV proteins have been identified and characterized for their ability to maintain immune activation, the role of HIV-p17, a matrix protein involved in the viral replication, is still undefined. Results Here, we report that exposure of macrophages to recombinant human p17 induces the expression of proinflammatory and proatherogenic genes (MCP-1, ICAM-1, CD40, CD86 and CD36) while downregulating the expression of nuclear receptors (FXR and PPARγ) that counter-regulate the proinflammatory response and modulate lipid metabolism in these cells. Exposure of macrophage cell lines to p17 activates a signaling pathway mediated by Rack-1/Jak-1/STAT-1 and causes a promoter-dependent regulation of STAT-1 target genes. These effects are abrogated by sera obtained from HIV-infected persons vaccinated with a p17 peptide. Ligands for FXR and PPARγ counteract the effects of p17. Conclusions The results of this study show that HIV p17 highjacks a Rack-1/Jak-1/STAT-1 pathway in macrophages, and that the activation of this pathway leads to a simultaneous dysregulation of immune and metabolic functions. The binding of STAT-1 to specific responsive elements in the promoter of PPARγ and FXR and MCP-1 shifts macrophages toward a pro-atherogenetic phenotype characterized by high levels of expression of the scavenger receptor CD36. The present work identifies p17 as a novel target in HIV therapy and grounds the development of anti-p17 small molecules or vaccines.

Ritonavir-induced lipoatrophy and dyslipidaemia is reversed by the anti-inflammatory drug leflunomide in a PPAR-γ-dependent manner.

BACKGROUND The complex interplay between viral infection and virus-activated inflammatory pathways with protease inhibitors (PIs) contributes to the increased risk of developing atherosclerosis and coronary artery disease in HIV-infected patients. Leflunomide is an antirheumatic drug whose administration to HIV-1-infected persons effectively decreases T-cell turnover and activation. In this study we have investigated the effects of leflunomide on dyslipidaemia and lipodistrophy induced by ritonavir in rodents. METHODS Mice were administered ritonavir (5 mg/kg/day) alone or in combination with leflunomide (40 mg/kg/day) for 12 days. Expression of nuclear receptor and lipidogenetic genes was measured in liver and adipose tissues. RESULTS Administration of the HIV PI ritonavir to mice increased plasma triacylglycerols, free fatty acids and cholesterol levels, and this effect was reverted by cotreatment with leflunomide. Ritonavir administration was associated with reduced epididymal fat/body weight ratio and increased liver content of triacylglycerols content. These effects were reverted by leuflunomide. Histopathology analysis shows that exposure to ritonavir causes inflammation of epididymal fat as demonstrated by dense leukocytes infiltration as well as by increased levels of proinflammatory mediators and reduced expression and activity of peroxisome proliferator-activated receptor-γ (PPAR-γ). Leflunomide reduced epididymal fat inflammatory-metabolic alteration induced by ritonavir and restored PPAR-γ expression in the epididymal fat. CONCLUSIONS We have shown that the anti-inflammatory drug leflunomide protects against ritonavir-induced inflammation and dysmetabolism in adipose tissue and might be a promising strategy in the setting of HIV-infected patients at risk for HIV-induced dyslipidaemia.

Reactivation of hepatitis B virus replication due to cytotoxic therapy: a five-year prospective study.

BACKGROUND AND AIMS In hepatitis B virus (HBV) carriers receiving chemotherapy, the risk of reactivation is high, particularly if rituximab is given alone or in combination with steroids. The aim of this study was to assess the incidence, prevalence, and clinical course of HBV infection in a cohort of patients with hematological malignancies receiving cytotoxic therapy as well as to propose a strategy for managing HBV reactivation. METHODS This is a prospective observational study. All consecutive patients with hematological malignancies receiving intravenous cytotoxic chemotherapy between October 2005 and June 2010 and followed up for at least six months were enrolled in the study. Viral hepatitis markers and liver function indexes were monitored prospectively. RESULTS We enrolled 478 patients, including 263 males (55%) and 465 (97.3%) Italians. Non-Hodgkins lymphoma was the most frequent diagnosis (66%). At least one HBV marker was positive in 96 patients (20%): 21 (4.4%) patients were HBsAg positive, 17 (3.5%) were anti-HBc positive, and 58 (12.1%) were anti-HBc/anti-HBs positive. All but one HBsAg-positive patient received therapy with nucleoside/nucleotide analogs prior to chemotherapy. All but three reached complete virological suppression at six months from the start of treatment. Of the 17 HBsAg-negative/anti-HBc-positive patients, three (18%) had reactivation with seroreversion. All three obtained viral suppression with adefovir. Regarding the 58 anti-HBc/anti-HBs-positive patients, two (3.4%) experienced seroreversion and were treated successfully with nucleoside analogs; both were taking rituximab. No severe ALT flares were observed during or after antiviral therapy. CONCLUSION Our data suggest that pre-treatment screening of patients at risk of viral reactivation yields benefit and therefore should be practiced by clinicians treating patients with malignancies.

HIV-1 infection is associated with changes in nuclear receptor transcriptome, pro-inflammatory and lipid profile of monocytes

BackgroundPersistent residual immune activation and lipid dysmetabolism are characteristics of HIV positive patients receiving an highly active antiretroviral therapy (HAART). Nuclear Receptors are transcription factors involved in the regulation of immune and metabolic functions through the modulation of gene transcription. The objective of the present study was to investigate for the relative abundance of members of the nuclear receptor family in monocytic cells isolated from HIV positive patients treated or not treated with HAART.MethodsMonocytes isolated from peripheral blood mononuclear cells (PBMC) were used for analysis of the relative mRNA expressions of FXR, PXR, LXR, VDR, RARα, RXR, PPARα, PPARβ, PPARγ and GR by Real-Time polymerase chain reaction (PCR). The expression of a selected subset of inflammatory and metabolic genes MCP-1, ICAM-1, CD36 and ABCA1 was also measured.ResultsMonocytes isolated from HIV infected patients expressed an altered pattern of nuclear receptors characterized by a profound reduction in the expressions of FXR, PXR, PPARα, GR, RARα and RXR. Of interest, the deregulated expression of nuclear receptors was not restored under HAART and was linked to an altered expression of genes which supports both an immune activation and altered lipid metabolism in monocytes.ConclusionsAltered expression of genes mediating reciprocal regulation of lipid metabolism and immune function in monocytes occurs in HIV. The present findings provide a mechanistic explanation for immune activation and lipid dysmetabolism occurring in HIV infected patients and could lead to the identification of novel potential therapeutic targets.

The HIV Matrix Protein p17 Promotes the Activation of Human Hepatic Stellate Cells through Interactions with CXCR2 and Syndecan-2

Background The human immunodeficiency virus type 1 (HIV-1) p17 is a matrix protein involved in virus lifes cycle. CXCR2 and Syndecan-2, the two major coreceptors for the p17 protein, are expressed in hepatic stellate cells (HSCs), a key cell type involved in matrix deposition in liver fibrotic disorders. Aim In this report we have investigated the in vitro impact of p17 on HSCs transdifferentiation and function and underlying signaling pathways involved in these processes. Methods LX-2 cells, a human HSC line, and primary HSC were challenged with p17 and expressions of fibrogenic markers and of p17 receptors were assessed by qRT-PCR and Western blot. Downstream intracellular signaling pathways were evaluated with qRT-PCR and Western blot as well as after pre-treatment with specific pathway inhibitors. Results Exposure of LX2 cells to p17 increases their contractile force, reshapes the cytoskeleton fibers and upregulates the expression of transdifferentiation markers including αSMA, COL1α1 and endothelin-1 through the activation of Jak/STAT and Rho signaling pathways. These effects are lost in HSCs pre-incubated with a serum from HIV positive person who underwent a vaccination with a p17 peptide. Confocal laser microscopy studies demonstrates that CXCR2 and syndecan-2 co-associate at the plasma membrane after exposure to p17. Immunostaining of HIV/HCV liver biopsies from co-infected patients reveals that the progression of liver fibrosis correlates with a reduced expression of CXCR2. Conclusions The HIV matrix protein p17 is pro-fibrogenic through its interactions both with CXCR2 and syndecan-2 on activated HSCs.

Urinary albumin-to-creatinine ratio is associated with endothelial dysfunction in HIV-infected patients receiving antiretroviral therapy

Endothelial dysfunction, a marker of cardiovascular (CV) risk, is common in human immunodeficiency virus (HIV)-infected patients. Microalbuminuria is frequent in HIV-infected patients, and is a predictor of renal impairment and CV risk. We investigated the association between microalbuminuria and endothelial dysfunction among HIV-infected patients receiving highly-active antiretroviral therapy (HAART). Endothelial function, measured by brachial artery flow-mediated dilatation (bFMD), and urine albumin-to-creatinine ratio (UACR), were measured in 170 HAART-treated HIV-infected adults. The relationship between UACR and bFMD was evaluated. The prevalence of increased UACR, defined by two cut-off levels (20 mg/g and 30 mg/g), was 29% and 17%. UACR was significantly higher while bFMD was lower among patients with metabolic syndrome (MS). UACR was associated with bFMD (r = −0.31; p < 0.001). This association was stronger in MS-patients (r = −0.44; p = 0.003). UACR above 20 mg/g was associated with an increased risk (OR 2.37, 95% CI 1.15–4.89, p = 0.020) of severely impaired bFMD (bFMD ≤ 2.1%). Patients with MS and increased UACR had the lowest bFMD compared with those with none or one of the two conditions. Microalbuminuria and endothelial dysfunction are positively associated in HIV-infected patients regardless of known confounders. The coexistence of microalbuminuria and MS amplifies their deleterious influence on endothelial function.

Management of Meningitis Caused by Multi Drug-Resistant Acinetobacter Baumannii: Clinical, Microbiological and Pharmacokinetic Results in a Patient Treated with Colistin Methanesulfonate.

This paper reports on a 71- year-old Caucasian male who underwent neurosurgery for an oligodendroglioma, followed by a cranial-sinus fistula and cerebrospinal fluid rhinorrhea. The clinical course was complicated due to an extensively drug-resistant Acinetobacter baumannii meningitis. The patient was treated with colistin methanesulfonate, intrathecal for 24 days and intravenous for 46 days. In addition, the patient received meropenem and teicoplanin to treat a urinary tract infection and a bacterial aspiration pneumonia. Cerebrospinal fluid trough colistin levels resulted above the MIC of A. baumannii. Colistin cerebrospinal fluid concentration did not increase over the treatment period. Meningitis was cured and A. baumannii eradicated. No side effects from the antimicrobial therapy were observed. In conclusion, this case highlights the issues in treating infections caused by resistant Gram negative bacteria and supports previous findings on the efficacy, pharmacokinetic and tolerability of intravenous and intrathecal colistin treatments.