Domenico Sansonno

Subcellular Localization, Stability, and trans-Cleavage Competence of the Hepatitis C Virus NS3-NS4A Complex Expressed in Tetracycline-Regulated Cell Lines

ABSTRACT A tetracycline-regulated gene expression system and a panel of novel monoclonal antibodies were used to examine the subcellular localization, stability, and trans-cleavage competence of the hepatitis C virus (HCV) NS3-NS4A complex in inducible cell lines. The NS3 serine protease domain and the full-length NS3 protein expressed in the absence of the NS4A cofactor were diffusely distributed in the cytoplasm and nucleus. Coexpression of NS4A, however, directed NS3 to the endoplasmic reticulum (ER) or an ER-like modified compartment, as demonstrated by colocalization with 3,3′-dihexyloxacarbocyanine iodide, protein disulfide isomerase, and calnexin, as well as subcellular fractionation analyses. In addition, coexpression with NS4A dramatically increased the intracellular stability of NS3 (mean protein half-life of 26 versus 3 h) and allowed for NS4A-dependent trans-cleavage at the NS4B-NS5A junction. Deletion analyses revealed that the hydrophobic amino-terminal domain of NS4A was required for ER targeting of NS3. These results demonstrate the importance of studying HCV proteins in their biological context and define a well-characterized cell culture system for further analyses of the NS3-NS4A complex and the evaluation of novel antiviral strategies against hepatitis C.

Pegylated interferon-α, ribavirin, and rituximab combined therapy of hepatitis C virus–related mixed cryoglobulinemia: a long-term study

This study illustrates the use and efficacy of a combination of pegylated interferon-alpha (Peg-IFN-alpha) and ribavirin (RBV), with or without rituximab (RTX), in hepatitis C virus (HCV)-related mixed cryoglobulinemia (MC). Twenty-two patients with HCV-related MC received Peg-IFN-alpha (2a: 180 mug or 2b: 1.5 mug/kg) weekly plus RBV (1000 or 1200 mg) daily for 48 weeks, and RTX (375 mg/m(2)) once a week for 1 month followed by two 5-monthly infusions (termed PIRR). Fifteen additional patients received Peg-IFN-alpha/RBV with the same modalities as the PIRR schedule. Complete response was achieved in 54.5% (12/22) and in 33.3% (5/15) of patients who received PIRR and Peg-IFN-alpha/RBV, respectively (P < .05). Clearance of HCV RNA and conversion of B-cell populations from oligoclonal to polyclonal in liver, bone marrow, and peripheral blood was maintained for up to 3 years in 10 of 12 (83.3%) and in 2 of 5 (40%) patients receiving PIRR and Peg-IFN-alpha/RBV, respectively (P < .01). Cryoproteins in 22.7% (5/22) of patients with PIRR and in 33.3% (5/15) with Peg-IFN-alpha/RBV persisted despite sustained HCV RNA clearance. No response occurred in remaining 5 patients of both groups. PIRR therapy is well tolerated and more effective than Peg-IFN-alpha/RBV combination in HCV-related MC. Its effect may last for more than 3 years.

Recommendations for the management of mixed cryoglobulinemia syndrome in hepatitis C virus-infected patients.

OBJECTIVE The objective of this review was to define a core set of recommendations for the treatment of HCV-associated mixed cryoglobulinemia syndrome (MCS) by combining current evidence from clinical trials and expert opinion. METHODS Expert physicians involved in studying and treating patients with MCS formulated statements after discussing the published data. Their attitudes to treatment approaches (particularly those insufficiently supported by published data) were collected before the consensus conference by means of a questionnaire, and were considered when formulating the statements. RESULTS An attempt at viral eradication using pegylated interferon plus ribavirin should be considered the first-line therapeutic option in patients with mild-moderate HCV-related MCS. Prolonged treatment (up to 72 weeks) may be considered in the case of virological non-responders showing clinical and laboratory improvements. Rituximab (RTX) should be considered in patients with severe vasculitis and/or skin ulcers, peripheral neuropathy or glomerulonephritis. High-dose pulsed glucocorticoid (GC) therapy is useful in severe conditions and, when necessary, can be considered in combination with RTX; on the contrary, the majority of conference participants discouraged the chronic use of low-medium GC doses. Apheresis remains the elective treatment for severe, life-threatening hyper-viscosity syndrome; its use should be limited to patients who do not respond to (or who are ineligible for) other treatments, and emergency situations. Cyclophosphamide can be considered in combination with apheresis, but the data supporting its use are scarce. Despite the limited available data, colchicine is used by many of the conference participants, particularly in patients with mild-moderate MCS refractory to other therapies. Careful monitoring of the side effects of each drug, and its effects on HCV replication and liver function tests is essential. A low-antigen-content diet can be considered as supportive treatment in all symptomatic MCS patients. Although there are no data from controlled trials, controlling pain should always be attempted by tailoring the treatment to individual patients on the basis of the guidelines used in other vasculitides. CONCLUSION Although there are few controlled randomised trials of MCS treatment, increasing knowledge of its pathogenesis is opening up new frontiers. The recommendations provided may be useful as provisional guidelines for the management of MCS.

Transarterial Chemoembolization Plus Sorafenib: A Sequential Therapeutic Scheme for HCV-Related Intermediate-Stage Hepatocellular Carcinoma: A Randomized Clinical Trial

BACKGROUND Recurrence of hepatocellular carcinoma (HCC) is a major problem after surgical or ablative treatments. The aim of this prospective, single-center, placebo-controlled, randomized, double-blind clinical study was to evaluate the effectiveness of transarterial chemoembolization (TACE) combined with sorafenib as a sequential treatment regimen in delaying time to progression (TTP) of intermediate-stage HCC in patients with chronic hepatitis C virus (HCV) infection. MATERIAL AND METHODS Between October, 2007 and January, 2011, 80 HCV-infected patients with Barcelona Clinic Liver Cancer stage B HCC underwent the TACE procedure. All had Child-Pugh class A disease. They were randomized 1:1 to receive sorafenib at a dose of 400 mg twice daily or placebo. Endpoints were the TTP and the rates of adverse events and toxicity. RESULTS Sixty-two of 80 patients (77%), 31 in the sorafenib group and 31 in the control group, completed the study. The median TTP was 9.2 months in the sorafenib group and 4.9 months in the placebo group (hazard ratio, 2.5; 95% confidence interval, 1.66-7.56; p < .001). Metachronous, multicentric HCC progression occurred less frequently in sorafenib-treated patients (p < .05). Adverse reactions to sorafenib caused withdrawal from the study of 9 (22%) patients. CONCLUSION A conventional TACE procedure followed by sorafenib treatment resulted in a significantly longer TTP in patients with intermediate-stage HCV-related HCC, with no unexpected side effects.

Antibodies to hepatitis C virus in essential mixed cryoglobulinaemia

Although essential mixed cryoglobulinaemia (EMC) is recognized to be frequently associated with chronic liver disease, aetiology and pathogenesis of liver damage remain unsolved questions. The purpose of this study was to assess the possible causative role of hepatitis C virus (HCV) in the liver impairment occurring in patients with EMC. Twenty‐six consecutive EMC patients were evaluated. All patients underwent percutaneous liver biopsy. Anti‐HCV antibodies were assayed by ELISA and supported by a recombinant immunoblotting assay (4‐RIBA). The prevalence of anti‐HCV antibodies in patients with and without chronic active liver disease (CALD) was compared. Anti‐HCV antibodies were detected in 13 patients (50%) by ELISA and confirmed in 11 of them (42.3%) by 4‐RIBA, the remaining two patients being indeterminate in the supportive assay. CALD correlated significantly with anti‐HCV antibodies: indeed. 7/11 (63.6%) anti‐HCV+ patients showed histological and clinical pictures of CALD. compared with 1/15 (6/6%) anti‐HCV− patients (P<0.01). With the exception of the patient who was found to be HBsAg+, no liver tissue expressed hepatitis B virus‐related antigens in the hepatocytes. Additional histological findings included discrete lymphoid aggregates in portal tracts, siderosis, fatty changes, hyperplasia of Kupffer cells. It can be concluded that chronic liver damage in EMC is frequently associated with anti‐HCV antibodies. Although the cause of EMC remains unknown, this study has obvious implications for clarifying the etiology of associated CALD and further supports the therapeutic use of interferons in this disease.

Detection of hepatitis C virus (HCV) proteins by immunofluorescence and HCV RNA genomic sequences by non-isotopic in situ hybridization in bone marrow and peripheral blood mononuclear cells of chronically HCV-infected patients

Immunofluorescence (IF) to detect HCV antigens and non‐isotopic in situ hybridization (NISH) to detect HCV RNA genome were carried out on bone marrow (BM) and peripheral blood (PB) mononuclear cells (MC) of 11 chronically HCV‐infected patients. In four patients (36.4%) HCV antigens were detected in monocytes macrophages as well as in B lymphocytes in both BMMC and PBMC. Positive T lymphocytes in BMMC were found in three of them, but only one patient showed positive T cells in PBMC. NISH invariably demonstrated minus and plus HCV RNA genomic strands either in monocytes macrophages or B and T lymphocytes in BMMC and PBMC in the four HCV antigen‐positive patients and in two further patients not expressing viral proteins in blood MC. IF signals appeared diffusely distributed within the cytoplasm, or as brilliant granules in distinct submembrane areas or else in cytoplasm membrane. Nuclei never stained. Similarly, NISH displayed HCV RNA accumulation restricted to MC cytoplasm only, nuclei being persistently negative. NISH, however, was unable to detect cell membrane signal. Infection of blood MC is a common event in naturally acquired HCV infection, since none of these patients was conditioned by immunomodulating or immunosuppressive therapies. No difference was found in terms of mean age, length of disease, anti‐HCV immune response, type and severity of chronic liver damage between patients with HCV‐infected MC and patients without cell infection. These results demonstrate that HCV can infect BMMC and PBMC that represent important extrahepatic sites of virus replication, and may help to explain the immunological abnormalities observed in chronic HCV carriers.

Therapy for Hepatitis C Virus–Related Cryoglobulinemic Vasculitis

Cryoglobulins are present in about a quarter of patients with hepatitis C; in some, cryoglobulinemia can become symptomatic or even life-threatening. This review summarizes evolving therapy for the disorder, including new therapeutic options that are becoming available.

H. pylori infection and gastric cancer: state of the art (review).

Gastric cancer (GC) is one of the leading types of cancer worldwide, particularly in East Asian populations. Helicobacter pylori (HP) infection has been established as a major risk factor for GC. Although more than 50% of the world population is infected with this bacterium, less than 2% develop GC. Therefore, further risk factors (such as host genetic polymorphisms and lifestyle, as well as environmental and epigenetic factors) may also play a role in its occurrence. The correlation between HP infection and GC represents a typical model of a multi‑step process, characterized by some pre-neoplastic lesions with a high risk of progression (atrophic gastritis, intestinal metaplasia and dysplasia). In addition, HP also plays an oncogenic role in the development of mucosa‑associated lymphoid tissue (MALT) lymphoma, that accounts for approximately 3% of all gastric tumors. Hyperplastic polyps often arise in patients with atrophic gastric mucosa and HP‑associated gastritis (25% of cases); however, their malignant transformation is rare (<3% of cases). A number of trials have demonstrated the possibility of cancer prevention through HP screening and eradication, particularly in high‑risk populations, whereas it may not be cost‑effective in areas of low risk. In this review, we discuss i) the complex pathogenetic mechanisms of gastric carcinogenesis in which HP is involved; ii) the main approaches to the diagnosis, prevention, surveillance and treatment of pre-malignant lesions associated with HP infection; iii) the most effective way to detect GC in its earlier stages; and iv) the most important contribution to reducing the burden of GC.

Intrahepatic B cell clonal expansions and extrahepatic manifestations of chronic HCV infection

B cell repertoire in three biological compartments (liver, bone marrow and peripheral blood) of 30 unselected patients chronically infected with HCV has been characterized. Restriction of humoral immune response defined by enrichment of B cell clonal expansions occurred in the liver of 15 patients (50%), in the bone marrow and peripheral blood of 2 (6.7%) and 8 (26.7%) patients, respectively. An in situ hybridization technique was developed for the detection of dominant B cell clones in patients with monoclonal expansions. It was shown that morphologically distinct B cell expansion contributes to the formation of intraportal follicle‐like structures. Sequence analyses of CDRH3 gene segments revealed a wide range of variations. Clones derived from the same founder were demonstrated simultaneously in the three compartments explored. The occurrence of B cell clonal expansions profoundly influenced the clinical expression of HCV infection, since it was associated with extrahepatic manifestations. In sharp contrast, no extrahepatic signs or disease occurred in patients without evidence of intrahepatic B cell clonalities. These findings emphasize the profound B cell function derangement in at least half of HCV‐infected patients. Thus, the restriction of V gene usage has a direct impact on the clinical spectrum of HCV infection.

Endocrine manifestations of hepatitis C virus infection

Chronic infection with hepatitis C virus (HCV) can result in both hepatic and extrahepatic disease and endocrine dysfunction represents an important class of HCV-related extrahepatic disease. The most frequently occurring—and clinically important—of these endocrine disorders are thyroid disease and type 2 diabetes mellitus. In this Review, we evaluate the evidence in support of a link between HCV infection and endocrine-system dysfunction, and discuss potential pathophysiological mechanisms. A meta-analysis of the literature has revealed significant associations between chronic HCV infection, thyroid autoimmunity and hypothyroidism. Furthermore, a high prevalence of thyroid cancer has been reported in HCV-positive patients. Several clinicoepidemiological studies have demonstrated that chronic HCV infection could lead to the development of type 2 diabetes mellitus, possibly as a result of HCV-induced metabolic disturbances. Some researchers have postulated that a type 1 T-helper -cell mediated immune response underpins the association of chronic HCV infection with endocrine disease. Indeed, the available data suggest that a common immunological, type 1 T-helper cell pattern of cytokine expression and activation (via interferon-γ) could provide the pathophysiological basis for this association. Nonetheless, additional studies will be necessary to elucidate fully all the mechanisms involved in HCV-related endocrine dysfunction.