Hepatitis C Virus and Hepatocellular Carcinoma: Pathogenetic Mechanisms and Impact of Direct-Acting Antivirals

INTRODUCTION: Globally, between 64 and 103 million people are chronically infected with Hepatitis C virus (HCV), with more than 4.6 million people in the United States and is associated with more than 15.000 deaths annually. Chronic infection can result in cirrhosis and hepatocellular carcinoma. EXPLANATION: Epidemiological studies have indicated that persistent infection with hepatitis C virus (HCV) is a major risk for the development of hepatocellular carcinoma (HCC), mainly through chronic inflammation, cell deaths, and proliferation. Despite the new direct-acting antiviral drugs (DAA's) being able to clear the HCV, HCC recurrence rate in these patients is still observed. CONCLUSION: In this review we highlighted some aspects that could be involved in the onset of HCV-induced HCC such as immune system, viral factors and host genetics factors.Moreover, we focused on some of the last reports about the effects of DAA's on the HCV clearance and their potential implications in HCC recurrence

Modulation of tryptophan/serotonin pathway by probiotic supplementation in human immunodeficiency virus-positive patients: preliminary results of a new study approach

Background: To date, no data are available regarding the effects of probiotics on the pathway of tryptophan/serotonin metabolism among human immunodeficiency virus (HIV) 1–infected individuals. Because a condition of dysbiosis might be responsible for the altered use of tryptophan described in this population, the aim of this study was to investigate the link between probiotic supplementation and serotonin levels in combined antiretroviral therapy–treated patients and the subsistence of an interplay with inflammation. Methods: We conducted a pilot study that included 8 HIV-positive subjects. We collected blood and fecal samples before and after 6 months of probiotic supplementation, to measure the level of serotonin in serum and tryptophan in stool, the expression of CD38 and HLADR on peripheral CD4+ T lymphocytes (as immune activation markers), the expression of indoleamine 2,3-dioxygenase 1 messenger RNA (mRNA) and IFN-γ mRNA (as markers of tryptophan metabolism and systemic inflammation). Results: After probiotic supplementation, we observed a significant increase in concentration of serum serotonin (P=.008) and a decreased level of tryptophan in plasma. Moreover, a significant reduction in CD38 and HLA-DR expression on the surface of peripheral CD4+ T cells (P=.008) and a reduced expression of indoleamine 2,3-dioxygenase 1 mRNA on peripheral blood mononuclear cells (P=.04) were observed. Conclusions: Considering that this probiotic (Vivomixx® in EU; Visbiome® in USA) has an influence on tryptophan metabolism, larger studies on this topic are needed

VI Seminario di studio. Salute globale e scenari attuali. Nuovi contributi di ricerca. Istituto Superiore di Sanità. Roma, 16 aprile 2015. Riassunti

Esiste un bisogno crescente di chiare evidenze scientifiche che possano supportare le politiche per la salute. Questo vale per una serie di aspetti che vanno dai protocolli diagnostici applicati alle malattie trasmissibili, agli approcci terapeutici, agli studi epidemiologici, alla definizione e identificazione dei determinanti della salute con partico lare riguardo alle situazioni di grave diseguaglianza, alle contaminazioni ambientali, alla relazione tra malattia e diritti così come alla relazione tra malattia e diritto. L’obiettivo del Dottorato di Ricerca in Malattie Infettive, Microbiologia e Scienze della Salute è proprio quello di fornire momenti di crescita, finalizzati alla formazione di nuovi ricercatori, nel campo delle malattie infettive, della microbiologia, della parassitologia, della sanità pubblica e medicina sociale, nella medicina legale e nelle scienze forensi. L’obiettivo di questo sesto appuntamento, nell’ambito della collaborazione tra Istituto Superiore di Sanità e l’Università̀ Sapienza di Roma, con i dottorandi è proprio quello di fornire una cornice il più possibile unitaria a un quadro complesso di ricerche di base e applicate nell’ambito degli obiettivi del dottorato.There is a growing need for clear scientific evidence that can support health policies. This applies to a number of issues including diagnostic protocols applied to communicable diseases, therapeutic approaches, epidemiological studies, the definition and identification of the health determinants (with particular reference to situations of severe inequality), environmental contamination, the relationship between disease and rights as well as the relationship between disease and law. The objective of the PhD Program in Infectious Diseases, Microbiology and Health Sciences is precisely to provide moments of intellectual growth, aimed at the trai ning of new researchers in the field of infectious diseases, microbiology, parasitology, public health and social medicine, in forensic medicine and forensic sciences. The objective of the sixth meeting with graduate students, part of the collaboration between the Italian National Institute of Health, and the Sapienza University of Rome, is precisely to provide a frame as unitary as possible to a complex picture of basic and applied research within the objectives of the doctorat

What happens to cardiovascular system behind the undetectable level of HIV viremia?

Despite the combined antiretroviral therapy has improved the length and quality of life of HIV infected patients, the survival of these patients is always decreased compared with the general population. This is the consequence of non-infectious illnesses including cardio vascular diseases. In fact large studies have indicated an increased risk of coronary atherosclerotic disease, myocardial infarction even in HIV patients on cART. In HIV infected patients several factors may contribute to the pathogenesis of cardiovascular problems: life-style, metabolic parameters, genetic predisposition, viral factors, immune activation, chronic inflammation and side effects of antiretroviral therapy. The same factors may also contribute to complicate the clinical management of these patients. Therefore, treatment of these non-infectious illnesses in HIV infected population is an emerging challenge for physicians. The purpose of this review is to focus on the new insights in non AIDS-related cardiovascular diseases in patients with suppressed HIV viremia

Trans-dissemination of exosomes from HIV-1-infected cells fosters both HIV-1 trans-infection in resting CD4+T lymphocytes and reactivation of the HIV-1 reservoir

Abstract Intact HIV-1 and exosomes can be internalized by dendritic cells (DCs) through a common pathway leading to their transmission to CD4? T lymphocytes by means of mechanisms defined as trans-infection and trans- dissemination, respectively. We previously reported that exosomes from HIV-1-infected cells activate both unin- fected quiescent CD4? T lymphocytes, which become permissive to HIV-1, and latently infected cells, with release of HIV-1 particles. However, nothing is known about the effects of trans-dissemination of exosomes pro- duced by HIV-1-infected cells on uninfected or latently HIV-1-infected CD4? T lymphocytes. Here, we report that trans-dissemination of exosomes from HIV-1-infected cells induces cell activation in resting CD4? T lympho- cytes, which appears stronger with mature than immature DCs. Using purified preparations of both HIV-1 and exo- somes, we observed that mDC-mediated trans-dissemina- tion of exosomes from HIV-1-infected cells to resting CD4? T lymphocytes induces efficient trans-infection and HIV-1 expression in target cells. Most relevant, when both mDCs and CD4? T lymphocytes were isolated from combination anti-retroviral therapy (ART)-treated HIV-1- infected patients, trans-dissemination of exosomes from HIV-1-infected cells led to HIV-1 reactivation from the viral reservoir. In sum, our data suggest a role of exosome trans-dissemination in both HIV-1 spread in the infected host and reactivation of the HIV-1 reservoir. & Maurizio Federico [email protected] 1 Introduction HIV-1 can be delivered to uninfected target cells by den- dritic cells (DCs) through a process referred to as trans- infection [1, 2], which is mediated by the formation of virological synapses containing HIV-1-loaded DCs and target CD4? T lymphocytes [3, 4]. DCs support HIV-1 replication poorly, which is mostly a consequence of the intracellular expression of the Sam domain and HD domain-containing protein (SAMHD)-1 cell restriction factor, which acts by a twofold mechanism, i.e., by limiting the availability of triphosphate-dNTP needed for reverse transcription [5] and by degrading incoming viral RNA [6]. On the other hand, DCs can deliver intact HIV-1 viral particles to target cells in the absence of viral infection. Exactly how virions are transported by DCs is still a matter of debate. Fluorescence microscopy studies have indicated that viral particles are stored in non-acidic tetraspanin-rich (i.e., CD9?, CD63?, CD81?) endosomal compartments before their retrograde delivery to target cells [7]. It has also been hypothesized that viral particles traffic to invaginated pockets [8] that are partially accessible to proteases but exclude neutralizing antibodies [9]. Trans- infection efficiency differs between immature (i) and mature (m)DCs [10]. Most of the HIV-1 particles captured by iDCs are delivered to lysosomes for degradation. Con- versely, the interaction between CD169, which is highly expressed by mDCs [11, 12], and both monosialotetra- hexosylganglioside (GM)-1 [13] and GM-3 [14] embedded in the viral membrane favors the trafficking of virions to non-acidic vesicular compartments of mDCs that are con- tiguous with the extracellular milieu. Exosomes are vesicles of 50-100 nanometers that are released by all cell types [for a recent review, see reference 15]. They are generated by invagination of endosome National Center for Global Health, Istituto Superiore di Sanita`, Viale Regina Elena, 299, 00161 Rome, Italy 2 Department of Public Health and Infectious Diseases, ‘Sapienza’ University of Rome, Rome, Italy 123 membranes, leading to the formation of intraluminal vesi- cles which then become part of multivesicular bodies. They can traffic either to lysosomes for degradation or to the plasma membrane, thereby releasing their vesicular con- tents upon membrane fusion. Exosomes are part of the intercellular communication network [16]. They incorpo- rate messenger RNAs, microRNAs, and proteins, which can be active in target cells [17]. As a consequence, exo- somes play a key role in both physiological and patho- logical processes. An increasing body of literature supports the idea that exosomes are involved in the mechanisms of HIV-1-related pathogenesis [18–20]. On this subject, we previously demonstrated that the expression of HIV-1 Nef induces the release of exosomes incorporating active ADAM (a disin- tegrin and metalloprotease) 17 [21], i.e., a multi-domain, transmembrane, Zn2?-dependent proteinase whose most studied function is processing pro-tumor necrosis factor (TNF)a to its active form [22]. Resting CD4? T lympho- cytes targeted by exosome-associated ADAM17 are induced to release TNFa. This initiates events leading to activation of quiescent human primary CD4? T lympho- cytes, which thereby become competent for HIV-1 expression and replication [23–25]. Similar to HIV-1, exosomes also can be captured by DCs and delivered to bystander cells through a mechanism referred to as trans-dissemination [26]. It has been reported that both trans-infection and trans-dissemination recognize a similar intracellular pathway, since HIV-1 and exosomes are both retained in the same CD81? intracellular com- partments. Although it is known that exosomes and HIV-1 particles compete for the same pathway for entry into DCs [26], little is known about the virological consequences of trans-dissemination. We sought to fill this gap by investi- gating the effects on trans-infection of the DC-mediated delivery of exosomes from HIV-1-infected cells. Here, we provide evidence that mDC-mediated delivery of exosomes from HIV-1-infected cells induces cell activation and HIV- 1 permissiveness in resting primary CD4? T lymphocytes, as well as HIV-1 reactivation in the viral reservoir

Analysis of Th17 and Tc17 Frequencies and Antiviral Defenses in Gut-Associated Lymphoid Tissue of Chronic HIV-1 Positive Patients

The complex relationship between both the Th1/Th17 and Tc1/Tc17 axis and innate defences in the intestinal mucosa during HIV-1 infection has not been well characterized. This study examined the frequency, phenotype, and functional status of T cell populations in the gut-associated lymphoid tissue and peripheral blood of virologically suppressed HIV-1-infected patients on therapy, focusing on the Th1, Th17, Tc1, and Tc17 cell subsets. We found a persistent immune cell activation (CD38 and HLADR expression) into the GALT despite the higher levels of Th17 and Tc17 in respect to peripheral blood. An upregulation of type I IFN response in GALT compared to the peripheral blood compartment was also recorded. Furthermore, IFN-α/β levels were negatively related to the frequencies of Th1 naïve cells and Tc1 cell subsets (naïve, central memory, and effector memory) in the GALT. In contrast, no relationships between type I IFN response and Th1 or Tc1 cell subsets in peripheral blood compartment and between IFN-α/β and Th17/Tc17 in both GALT and peripheral blood district were recorded. These data indicate that prolonged antiretroviral treatment improves GALT immune function despite the persistence of immune activation and type I IFN response in chronic HIV-1 positive patients

Enantioselective Aza-Michael Addition of Imides by Using an Integrated Strategy Involving the Synthesis of a Family of Multifunctional Catalysts, Usage of Multiple Catalysis, and Rational Design of Experiment

A challenging asymmetric reaction (aza-Michael addition of imides to enones) has been optimized through an integrated approach involving the synthesis of a family of organocatalysts, multiple catalysis (usage of additives), and finally with rational exploration of the chemical space by the application of the experiment design

Direct-acting antiviral therapy enhances total CD4+ and CD8+ T-cells responses, but does not alter T-cells activation among HCV mono-infected, and HCV/HIV-1 co-infected patients

AIM: Chronic immune activation and poor T-cell immune response are strongly associated with disease progression and pathogenesis of both hepatitis C virus (HCV) and human immunodeficiency virus (HIV)-1 infections. Little is known about the impact of anti-HCV Interferon (IFN)-free direct-acting antiviral (DAA) therapy on the systemic T-cells activation and patterns of peripheral T-cells producing pro-inflammatory cytokines. PATIENTS AND METHODS: Forty-five subjects including 18 HCV mono-infected, 17 HCV/HIV-1 co-infected patients under antiretroviral therapy (ART), and 10 healthy controls (HCs) were recruited. Blood samples were collected at baseline (T0) and 12 weeks after the end of DAA therapy (T1). Cell phenotypes (CD3, CD4, CD8), activation markers (CD38 and HLA-DR), and frequency of IFN-γ, interleukin (IL)-17, and IL-22 producing CD4+ and CD8+ T-cells were measured by flow cytometry. Plasma levels of related cytokines were also measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Both HCV, and HCV/HIV-1 patients before and after therapy, showed significant higher percentages of any T-cell subset expressing CD38 and/or HLA-DR compared to HCs. No differences were observed in T-cells activation at T1 compared to T0 in patient groups, and when HCV patients were compared to HCV/HIV-1 group (P>0.05). After therapy, the potential of total circulating T helper (Th) and T cytotoxic (Tc) cells producing IFN-γ, IL-17, and IL-22 were increased. Plasma level of IFN-γ at baseline was showed difference compared to HCs, and significantly reduced after therapy (P<0.05). CONCLUSION: Total T-cells immune response enhances after therapy, however, the state of immune activation may remain elevated for a longtime after the end of treatment and contribute to post-Sustained Virologic Response (SVR) consequences

Impact of High-Dose Multi-Strain Probiotic Supplementation on Neurocognitive Performance and Central Nervous System Immune Activation of HIV-1 Infected Individuals

Gut microbiota has metabolic activity which influences mucosal homeostasis, local and systemic immune responses, and other anatomical systems (i.e., brain). The effects of dysbiosis are still poorly studied in Human Immunodeficiency Virus-1 (HIV-1) positive subjects and insufficient data are available on the impairment of the gut-brain axis, despite neurocognitive disorders being commonly diagnosed in these patients. This study evaluated the impact of a probiotic supplementation strategy on intrathecal immune activation and cognitive performance in combined antiretroviral therapy (cART) treated HIV-1 infected subjects

Direct-acting antiviral therapy enhances total CD4+ and CD8+ T-cells responses, but does not alter T-cells activation among HCV mono-infected, and HCV/HIV-1 co-infected patients

AIM: Chronic immune activation and poor T-cell immune response are strongly associated with disease progression and pathogenesis of both hepatitis C virus (HCV) and human immunodeficiency virus (HIV)-1 infections. Little is known about the impact of anti-HCV Interferon (IFN)-free direct-acting antiviral (DAA) therapy on the systemic T-cells activation and patterns of peripheral T-cells producing pro-inflammatory cytokines. PATIENTS AND METHODS: Forty-five subjects including 18 HCV mono-infected, 17 HCV/HIV-1 co-infected patients under antiretroviral therapy (ART), and 10 healthy controls (HCs) were recruited. Blood samples were collected at baseline (T0) and 12 weeks after the end of DAA therapy (T1). Cell phenotypes (CD3, CD4, CD8), activation markers (CD38 and HLA-DR), and frequency of IFN-γ, interleukin (IL)-17, and IL-22 producing CD4+ and CD8+ T-cells were measured by flow cytometry. Plasma levels of related cytokines were also measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: Both HCV, and HCV/HIV-1 patients before and after therapy, showed significant higher percentages of any T-cell subset expressing CD38 and/or HLA-DR compared to HCs. No differences were observed in T-cells activation at T1 compared to T0 in patient groups, and when HCV patients were compared to HCV/HIV-1 group (P>0.05). After therapy, the potential of total circulating T helper (Th) and T cytotoxic (Tc) cells producing IFN-γ, IL-17, and IL-22 were increased. Plasma level of IFN-γ at baseline was showed difference compared to HCs, and significantly reduced after therapy (P<0.05). CONCLUSION: Total T-cells immune response enhances after therapy, however, the state of immune activation may remain elevated for a longtime after the end of treatment and contribute to post-Sustained Virologic Response (SVR) consequences