PubMed Health⌕ Search

Biomedical subjects

A L Zignego

Publications and source records attributed to A L Zignego.

At least 19 recordsLinked to original sources

Modifications of plasma platelet-activating factor (PAF)-acetylhydrolase/PAF system activity in patients with chronic hepatitis C virus infection.

Hepatitis C virus (HCV) chronically infects about 200 million individuals worldwide and leads to severe liver and lymphatic diseases. HCV circulates in the serum, associated with apoB-containing lipoproteins. Platelet-activating factor (PAF), a pro-inflammatory mediator, is mainly modulated by plasma PAF-acetylhydrolase (pPAF-AH), associated with ApoB100-containing low-density lipoproteins (LDL). The aim of the study was to evaluate the potential effects of chronic HCV infection on the PAF/pPAF-AH system. HCV-RNA was detected in plasma, peripheral blood mononuclear cells (PBMC) and liver samples. Plasma PAF levels, pPAF-AH activity, ApoB100 serum titres and pPAF-AH mRNA levels in cultured macrophages were determined. Plasma PAF levels were significantly higher and pPAF-AH activity was significantly lower in HCV patients than in controls. No significant modifications of pPAF-AH mRNA in macrophages or in ApoB100 values were observed in HCV patients compared with controls. Patients who cleared HCV after antiviral treatment showed a complete restoration of pPAF-AH activity and significant decrease of PAF levels during the follow-up. No data exist about the PAF/pPAF-AH system behaviour during HCV infection. This study shows that in HCV patients modifications of pPAF-AH activity/PAF levels take place and that HCV clearance restored pPAF-AH activity. This suggests that circulating viral particles play a role in PAF/pPAF-AH system modifications and such an alteration could be involved in HCV-related damage.

1-Alkyl-2-acetylglycerophosphocholine Esterase↗

Extrahepatic manifestations of Hepatitis C Virus infection: a general overview and guidelines for a clinical approach.

Hepatitis C Virus is associated with a wide series of extrahepatic manifestations. Based on available data the link between the virus and some of these extrahepatic diseases is only suggested and needs further confirmation. Hepatitis C Virus-related lymphoproliferative disorders, whose prototype is mixed cryoglobulinaemia, represent the most closely related extrahepatic manifestations of Hepatitis C Virus. Other Hepatitis C Virus-associated disorders include nephropathies, thyreopathies, sicca syndrome, idiopathic pulmonary fibrosis, porphyria cutanea tarda, lichen planus, diabetes, chronic polyarthritis, cardiopathy and atherosclerosis. A pathogenetic link between Hepatitis C Virus and some extrahepatic manifestations was confirmed by their responsiveness to antiviral therapy, which is now deemed the first therapeutic option to consider. By contrast, there are diseases where treatment with interferon was ineffective or dangerous. The aim of the present paper is to outline the most recent evidence concerning extrahepatic disorders that are possibly associated with Hepatitis C Virus infection. Special emphasis will be given to discussion of the most appropriate clinical approaches to be adopted in order to diagnose, treat (possibly prevent) and follow-up extrahepathic diseases in patients with Hepatitis C Virus infection.

Autoimmune Diseases↗

Low serum tryptophan levels, reduced macrophage IDO activity and high frequency of psychopathology in HCV patients.

Indoleamine 2,3-dioxygenase (IDO), a key enzyme of tryptophan (TRP) metabolism, is induced in various tissues of patients with bacterial and viral infection or with neoplastic diseases. This induction is considered the main cause of the decreased serum TRP levels, the reduced brain serotonin synthesis and the occurrence of psychopathological disorders often detected in patients with chronic infections or different forms of cancer. We studied 89 subjects including: (a) 39 patients with chronic hepatitis C virus (HCV) infection and mild liver damage (b) 40 healthy controls, and (c) 10 patients with chronic hepatitis B virus (HBV) infection. We measured serum TRP and kynurenine levels and IDO activity in macrophages. Furthermore, each patient had an accurate psychopathological evaluation. HCV-infected patients had lower (-28%) serum TRP concentrations than healthy volunteers or HBV-infected patients with comparable liver damage. Depression and anxiety symptoms were particularly common in HCV patients. Unexpectedly, serum kynurenine levels and IDO activity in cultured macrophages (under both basal or stimulated conditions) were lower in HCV patients than in controls. Our study shows that HCV patients have reduced serum TRP levels and confirms that they frequently suffer from anxiety and depression-related symptoms. The reduced IDO activity found in the macrophages of these patients suggest that HCV infection may hamper macrophage functions.

Adult↗

Anti-hepatitis A virus seroprevalence and seroconversion in a cohort of patients with chronic viral hepatitis.

BACKGROUND: Patients with chronic hepatitis C infected by hepatitis A virus have a substantial risk of fulminant hepatitis or death, while the course of hepatitis A virus is uncomplicated in most subjects with chronic hepatitis B. AIM: To evaluate the prevalence of anti-hepatitis A virus antibodies and the incidence of hepatitis A virus seroconversion in a nationwide sample of 530 patients with chronic hepatitis B and/or hepatitis C infection initially susceptible to this infection after a follow-up of some years. RESULTS: The overall anti-hepatitis A virus prevalence was 85.7%, with no difference between males and females. By the age of 50 years, almost all patients were found to have been exposed to hepatitis A virus. After a mean follow-up period of 76 months the overall anti-hepatitis A virus seroconversion rate in the 76 initially susceptible individuals was 1.2 per 100 person/years. However, it was 0.3 per 100 person/years in those hepatitis B surface antigen positive but 3.36 per 100 person/years in those anti-hepatitis C virus positive. None of the seroconverters was affected by a clinically evident disease or showed deterioration of underlying chronic liver disease. CONCLUSIONS: The present study shows that Italian patients >50 years of age with chronic liver disease have already been exposed to hepatitis A virus suggesting that anti-hepatitis A virus screening is not advisable in these subjects.

Adolescent↗

Cryoglobulins.

Serum cryoglobulins are found in a wide spectrum of disorders but are often transient and without clinical implications. Monoclonal cryoglobulins are usually associated with haematological disorders, whereas mixed cryoglobulins are found in many infectious and systemic disorders. So called essential mixed cryoglobulinaemia shows a striking association with hepatitis C virus (HCV) infection (> 90%). It is a systemic vasculitis (leucocytoclastic vasculitis) with cutaneous and multiple visceral organ involvement. Chronic HCV infection can lead to a constellation of autoimmune and neoplastic disorders. In this review, the aetiology, diagnosis, disease heterogeneity, and treatment of cryoglobulinaemia are discussed.

Autoimmunity↗

T(14;18) translocation in chronic hepatitis C virus infection.

Pathogenic mechanisms of B-cell lymphoproliferative disorders in chronic hepatitis C virus (HCV) infection are unclear. We studied t(14;18) translocation by polymerase chain reaction in peripheral blood mononuclear cells from 50 patients with HCV-related liver disease (group A), 7 with mixed cryoglobulinemia syndrome (group B), 55 with HCV-negative liver disease (group C), and 30 with HCV-negative chronic rheumatic disorders or chronic infection by nonhepatotropic agents (group D). T(14;18) was significantly more frequent in group A (13/50 patients = 26 %) and group B (5/7 = 71.4%) patients than in group C (1/55 = 3.6%) and group D (1/30 = 3.3%) ones. Immunoblot analysis showed bcl-2 over-expression in all t(14;18)-positive samples. In group A, 10/13 (77%) patients with t(14;18) and 13/37 (35%) without t(14;18) had serum cryoglobulins in the absence of mixed cryoglobulinemia symptoms (P <.05). These data indicate that t(14;18) and bcl-2 over-expression in lymphoid cells are frequent in chronic HCV infection and suggest that this event may contribute to the pathogenesis of HCV-related lymphoproliferative disorders.

Aged↗

Relation between infection and autoimmunity in mixed cryoglobulinemia.

Mixed cryoglobulinemia (MC) is a systemic vasculitis of small to medium-sized vessels due to the vascular deposition of circulating immune-complexes (CIC) and complement. A leukocytoclastic vasculitis is the histologic hallmark of cutaneous manifestations of the disease, while a clonal B lymphocyte expansion in blood, bone marrow, liver, and spleen represents the underlying pathologic alteration responsible for the production of cryo-CIC and non-cryo CIC with rheumatoid factor activity. A causative role of hepatitis C virus (HCV) infection has been demonstrated in the large majority of MC patients. Hepatitis C virus is both a hepatotropic and a lymphotropic virus; due to this latter biological peculiarity, HCV may trigger a constellation of autoimmune-lymphoproliferative disorders. Besides MC, other important HCV-related diseases are porphyria cutanea tarda, autoimmune hepatitis, membranoproliferative glomerulonephritis, and B cell neoplasias. Hepatitis C virus-related MC represents a link between autoimmune and lymphoproliferative disorders; moreover, MC is an important model to study the complex relation between infections and immune system alterations in humans. During the last years many other autoimmune manifestations have been correlated with HCV infection; namely, sicca syndrome, chronic polyarthritis, polydermatomyositis, fibromyalgia, autoimmune thyroiditis, lung fibrosis, and diabetes mellitus. It is often difficult to verify whether the above associations are coincidental or a pathogenetic link actually exists. At least for particular patients' subsets and in some geographic areas, a causative role of HCV seems to be likely. The geographically heterogeneous distribution of HCV-related autoimmune diseases suggests the contribution of important environmental and genetic factors in the pathogenesis of such conditions. In clinical practice, patients with recent-onset, atypical rheumatic and autoimmune disorders should be carefully investigated for possible HCV infection; this is particularly advisable for correct diagnosis and adequate therapeutic strategy.

Autoimmunity↗

Prevalence of mixed infection by different hepatitis C virus genotypes in patients with hepatitis C virus-related chronic liver disease.

Multiple infection by different hepatitis C virus (HCV) genotypes may be of great clinico-pathologic interest. In this study we determined the effective prevalence of coinfections by two or more HCV genotypes in 213 subjects with HCV-positive chronic hepatitis by using genotype-specific polymerase chain reaction (PCR), genotype-specific probe hybridization, and direct sequencing. The most prevalent genotype was HCV-1b (54%). HCV-2 (a/c) was also prevalent (27%), and types 1a and 3a were found in 5% and 3% of patients, respectively. A mixed infection was detected in 23 patients (10.8%): 4 out of 23 were coinfected by types 1a + 1b, while the remaining 19 patients had a b + 2 (a/c) mixed infection. Further analysis based on restriction fragment length polymorphism (RFLP) on type-specific PCR products was used to verify genotyping results. Only four coinfections (1a + 1b in 2 patients and 1b + 2 (a/c) in the remaining 2 patients, respectively) were confirmed by enzyme cleavage. All patients with true coinfection had long-lasting infection and liver cirrhosis. Both true and false mixed infections resulting from RFLP analysis were confirmed by direct sequencing of type-specific amplification products. We also determined a recurrent C/T transversion at position 618 in all sequenced samples. In 4 cases another point mutation (G/A at position 626) was found, reducing the number of mismatches between HCV-2 and HCV-1b from 4 to 3 (or 2). Interestingly, all HCV-2 isolates sequenced showed the highest degree of nucleotide homology with HCV-2 subtype c, confirming the relatively high prevalence of this subtype in Italy. In conclusion, we showed the possibility of multiple infection by different HCV types in the general population of chronically infected patients without particular risk factors, even if in a low percentage of cases. Further studies are needed to assess the clinical relevance of chronic HCV infection with multiple genotypes.

Adult↗

Hepatitis C virus (HCV) in cryoglobulinaemic leukocytoclastic vasculitis (LCV): could the presence of HCV in skin lesions be related to T CD8+ lymphocytes, HLA-DR and ICAM-1 expression?

An association between mixed cryoglobulinaemia (MC) and hepatotropic viruses, chiefly hepatitis C virus (HCV), has been widely reported. The presence of HCV genomic sequences or HCV-related viral proteins in the serum, purified cryoglobulins, peripheral blood mononuclear cells and into several tissues has suggested an important triggering role for HCV in MC patients. However, only few reports investigated the presence of HCV in cutaneous vasculitis and its potential pathogenetic role. Biopsies of cutaneous purpuric lesions from 5 MC female patients (aged from 40 to 80 years) were carried out for virological and histopathological evaluation. A leukocytoclastic vasculitis pattern was found in 4/5 subjects, while the presence of HCV RNA was detected in 3/5. In only 3 cases biopsy specimens were sufficient for immunohistochemical and direct immunofluorescence (DIF) studies. Immunohistochemical evaluation was performed by means of alkaline phosphatase and monoclonal anti-alkaline phosphatase (APAAP) immune-complexes. In the same skin specimen APAAP and DIF findings were compared with the presence/absence of HCV genomic sequences (PCR technique). In 1 MC patient, the detection of HCV-RNA was associated to a prevalent CD8+ T suppressor pattern with a perivascular and subjunctional distribution as well as an intense expression of second class (HLA-DR) and intercellular adhesion (ICAM-1) molecules on basal keratinocytes, endothelial cells and perivascular infiltrate. These findings suggest a marked inflammatory activation that spreads from endothelial cells to keratinocytes and Langerhans cells. In the 2 HCV-RNA negative specimens the scanty immunopathological staining could indicate a residual activity due to the previous inflammatory event triggered by cryoglobulins. The deposition of circulating HCV-containing immune complexes (CIC) in the skin could be the initial pathogenic event for cryoglobulinemic vasculitis; subsequently CIC could spread from the vascular bed to the perivascular tissue and then could be very rapidly eliminated. If confirmed in larger patients' series these findings could definitely demonstrate a direct role of HCV in the pathogenesis of cryoglobulinemic vasculitis.

Adult↗

Prevalence of monoclonal gammopathies in patients with hepatitis C virus infection.

BACKGROUND: An association between monoclonal gammopathies and chronic liver diseases has been reported. OBJECTIVE: To determine the prevalence of monoclonal gammopathies in patients with chronic hepatitis C virus (HCV) infection and the possible association of monoclonal gammopathies with HCV genotypes. DESIGN: Prospective study. SETTING: Departments of internal medicine and hematology at two university hospitals in Italy. PATIENTS: 239 HCV-positive and 98 HCV-negative patients with chronic liver diseases were recruited consecutively. MEASUREMENTS: Clinical data were gathered, liver histologic examination was done, serum immunoglobulin and cryoglobulin levels were measured, and immunoelectrophoresis was done for monoclonal component detection. Patients with monoclonal gammopathy had serum HCV RNA measured and HCV genotype determined by polymerase chain reaction and had histologic examination of bone marrow. RESULTS: Monoclonal band was detected in 11% of HCV-positive patients and in 1% of HCV-negative patients (P = 0.004). The prevalence of HCV genotype 2a/c was higher in patients with monoclonal gammopathies than in those without (50% compared with 18%; P = 0.009). CONCLUSION: The prevalence of monoclonal gammopathies in patients with HCV-related chronic liver disease is striking and is often associated with genotype 2a/c infection.

Adolescent↗

Hepatitis C virus persistence in human hematopoietic cells injected into SCID mice.

The issue of infection of peripheral blood mononuclear cells (PBMC) by the hepatitis C virus (HCV) has potentially important implications, but is still debated. We have used the severe combined immunodeficiency (SCID) mouse model to test for the persistence of HCV in PBMC. Hematopoietic cells isolated from 14 subjects infected by HCV were inoculated intraperitoneally into SCID mice. Serum and blood cell samples from these mice were obtained with a mean follow-up of 8 weeks. As controls, human fibroblasts and sheep PBMC, preincubated with a human HCV-positive serum, were inoculated concomitantly into mice and analyzed. HCV-RNA positive strands were detected in 7 of 26 serum samples and 8 of 26 cell fractions from SCID mice inoculated with HCV-positive PBMC, after 8 weeks of follow-up. In contrast, no HCV RNA was detectable in the 10 control mice. HCV-RNA negative strands were detected in only 2 of 10 tested samples from 2 mice, and both positive mice had been inoculated with PBMC from HCV-positive subjects with malignant hematopoietic syndrome. Our study offers strong evidence for the persistence of HCV infection in mononuclear cells. Our results are also consistent with a low rate of HCV multiplication. This SCID mouse model might therefore be useful in analyzing the mechanisms of HCV persistence in mononuclear cells.

Animals↗

Interferon and thymosin combination therapy in naive patients with chronic hepatitis C: preliminary results.

AIMS/BACKGROUND: This randomized study was performed to compare the efficacy of interferon-alpha (IFN-alpha) + thymosin alpha 1 (Talpha1) treatment to that of IFN-alpha alone in light of biochemical and virological response of naive patients with chronic hepatitis C. METHODS: Seventeen patients were treated with IFN alpha-2b (3 million units MU three times a week) + Talpha1 (1 mg twice weekly); the other 17 patients received only IFN alpha-2b at the same dose. All patients were treated for 6 months and followed up for 12 months. Biochemical (ALT values) and virological (HCV-RNA) responses to treatment were determined. RESULTS: Combination therapy showed significantly higher efficacy than monotherapy in achieving biochemical and virologic end-of-treatment response (p<0.05). At 12 month follow-up, the sustained biochemical response was slightly greater in patients treated with combination therapy than in those treated with monotherapy. No significant difference in response by HCV-1b subtype was observed between the two treatment groups; however, HCV-2c subtype showed a trend to responding better to IFN-alpha+Talpha1 than to IFN-alpha alone. CONCLUSIONS: These data suggest that the immune modulator Talpha1 may be additive or synergistic with IFN-alpha in normalizing end-treatment biochemical and virological responses in patients with chronic hepatitis C. Higher doses and/or more prolonged courses may improve the sustained response rates to this treatment.

Adult↗

Mixed cryoglobulinaemia: a cross-road between autoimmune and lymphoproliferative disorders.

Mixed cryoglobulinaemia (MC) is a systemic vasculitis, secondary to the deposition in small and medium-sized blood vessels of circulating immune complexes, mainly the cryoglobulins, and complement. MC is characterised by a typical clinical triad (purpura, weakness, arthralgias) and by one or more organ involvement: chronic hepatitis, glomerulonephritis, peripheral neuropathy, skin ulcers and diffuse vasculitis. In a limited number of MC patients, a malignancy, that is B-cell non-Hodgkin's lymphoma or hepatocellular carcinoma, may also develop. Hepatitis C virus (HCV) infection has been found in the majority of patients with MC; the frequency of HCV markers (91%) was significantly higher than other rheumatic diseases (6.4%), namely systemic lupus, Sjögren's syndrome, rheumatoid arthritis and systemic sclerosis, or healthy controls (1.2%). The HCV infection of lymphoid tissues may represent the remote event leading to B-lymphocyte proliferation responsible for autoantibodies and immune-complex production. In a similar way, HCV infection may also be involved in the pathogenesis of other autoimmune (glomerulonephritis, thyroiditis, lung fibrosis, autoimmune hepatitis, porphyria cutanea tarda) and lymphoproliferative disorders (monoclonal gammopathies, B-cell lymphomas). MC shares numerous clinico-serological and pathological features with the above disorders. HCV seems to be their common etiological agent; however, a variable combination of unknown co-factors (infectious, genetic, environmental) should be determinant for the appearance of different clinical patterns.

Autoimmune Diseases↗

Vertical transmission of HCV.

BACKGROUND: Knowledge about vertical transmission of HCV is still limited. In this study we followed up the virological status of a series of offspring born to anti-HCV positive, anti-HIV negative mothers. METHODS: Between January 1993 and January 1995, 5000 consecutive, anti-HIV negative pregnant women were screened for anti-HCV (ELISA III) and all positive samples were confirmed by RIBA III and analyzed for HCV-RNA by polymerase chain reaction (PCR). Babies born to anti-HCV positive mothers were followed from birth to two years by testing for ALT levels, anti-HCV antibodies and HCV-RNA. RESULTS: Of 5000 mothers 80 (1.6%) were anti-HCV positive (ELISA III) and RIBA III positive. Of these, 56 (70%) were HCV-RNA positive. We examined 80 babies, born to anti-HCV positive mothers: 56 with HCV-RNA positive mothers and 24 with HCV-RNA negative mothers. Two babies (3.6%) of 56 were anti-HCV and HCV-RNA positive, with normal liver function tests. Seventy-eight babies (97.5%) of 80 (54 with HCV-RNA positive mothers and 24 with HCV-RNA negative mothers) were HCV-RNA negative, with normal liver function tests and detectable levels of anti-HCV antibodies that gradually disappeared between 8-12 months. CONCLUSION: Mother-to-infant transmission of HCV is possible only in the case of HCV-RNA positive mothers. In our study the rate of transmission is 3.6%, (2/56 babies with HCV-RNA positive mothers). HCV transmission may occur without evident association with breast-feeding or vaginal delivery.

Enzyme-Linked Immunosorbent Assay↗