Clinical significance of enlarged perihepatic lymph nodes in chronic hepatitis B

GOALS: To evaluate the clinical significance of enlarged perihepatic lymph nodes in patients with chronic hepatitis B. BACKGROUND: Enlargement of perihepatic lymph node is a common finding during ultrasonography in patients with chronic hepatitis. Its relation with liver histology and viremia was reported in chronic hepatitis C, but little has been known about its clinical significance in chronic hepatitis B. STUDY: We evaluated the clinical significance of perihepatic lymphadenopathy in chronic hepatitis B. In 50 patients with biopsy-proven chronic hepatitis B and 15 healthy controls, the perihepatic lymph node volume was evaluated by ultrasonography and its possible correlation with biochemical tests, hepatitis activity index, and hepatitis B viremia was investigated. RESULTS: Perihepatic lymph node was detected in 48 of 50 patients with chronic hepatitis B (volume = 3.4 +/- 2.4 mL) and in two of 15 controls (0.4 mL and 0.6 mL). In chronic hepatitis B, lymph node volume showed a significant correlation with serum aspartate transaminase (r = 0.66), alanine transaminase (r = 0.63), gamma-glutamyl-transpeptidase (r = 0.53), histologic activity index (r = 0.59), and necroinflammatory score (r = 0.59; p < 0.05 for all), but not with fibrosis score and serum hepatitis B viremia. CONCLUSIONS: Enlarged perihepatic lymph nodes in chronic hepatitis B can be a good indicator for histologic and biochemical inflammatory activity of the liver, but not for viremia.     

Perihepatic lymphadenopathy in chronic hepatitis C: A complementary diagnostic element?

BACKGROUND AND AIMS: The authors searched for perihepatic lymph nodes during ultrasonography performed for other symptoms in 1222 Sicilian outpatients in order to assess the incidence and possible significance of the association of perihepatic lymph nodes and chronic hepatitis C. METHOD: One or two lymph nodes were observed in 184/1222 patients, and 142 of these 184 were anti-hepatitis C virus (HCV) positive. RESULTS: Our results confirmed a very high incidence of perihepatic lymphadenopathy during chronic hepatitis. The concomitant presence of HCV virus and perihepatic lymph nodes may confirm the marked lymphotropism of this virus. CONCLUSION: As anti-HCV positivity is frequent in asymptomatic subjects with normal alanine aminotransferase concentrations, the authors believe that searching for sentinel perihepatic lymph nodes during abdominal ultrasonography could be recommended in routine diagnostic screening for HCV infection. Any perihepatic lymph nodes detected by this method could pinpoint subjects for whom more specific examinations are required, especially in areas where the virus is particularly endemic.     

Occult persistence and lymphotropism of hepatitis C virus infection

Recent discovery of occult hepatitis C virus （HCV） infection persisting after spontaneous or antiviral therapy-induced resolution of hepatitis C was made possible by the introduction of nucleic acid amplification assays capable of detecting HCV RNA at sensitivities superseding those offered by clinical tests. Although individuals with this seemingly silent HCV infection are usually anti-HCV antibody reactive and have normal liver function tests, occult HCV infection has also been reported in anti-HCV-negative individuals with persistently elevated liver enzymes of unknown etiology. Studies have shown that HCV RNA can persist for years in serum, lymphomononuclear cells and liver in the absence of clinical symptoms, although histological evidence of a mild inflammatory liver injury can be occasionally encountered. Furthermore, while HCV RNA can be detected in circulating lymphoid cells in approximately 30% of cases, a short-term culture under stimulatory conditions augments HCV replication in these cells allowing detection of virus in otherwise HCV-negative cases. HCV infects different immune cell subsets, including CD4^＋ and CD8^＋ T lymphocytes, B cells and monocytes. Studies employing clonal sequencing and single-stranded conformational polymorphism analyses have revealed unique HCV variants residing in immune cells, further strengthening the notion of HCV lymphotropism. Overall, the data accumulated suggest that occult HCV infection is a common consequence of resolution of symptomatic hepatitis C and that examination of the cells of the immune system is an effective approach to diagnosis of HCV infection and its long-term persistence. Further work is required to fully realize pathogenic and epidemiological consequences of occult HCV persistence.     

Sonographic detection of perihepatic lymph nodes: technique and clinical value

Sonographic detection of perihepatic lymphadenopathy by transabdominal ultrasound is helpful in the diagnosis of acute and chronic liver disease but differentiation between benign inflammatory and malignant disease is not possible. The diagnostic value of perihepatic lymphadenopathy has been evaluated in patients with chronic hepatitis C and primary biliary cirrhosis. In patients with chronic hepatitis C enlargement of perihepatic lymph nodes is associated with viremia and is predictive for the presence of severe inflammatory activity with and without cirrhosis. In retrospective studies it could be shown that patients with chronic hepatitis C without response to antiviral therapy do not normalize the size of perihepatic lymph nodes. Future prospective studies have to evaluate whether successful antiviral therapy together with histological improvement will be reflected in an decline of perihepatic lymph node size. In patients with primary biliary cirrhosis the total perihepatic lymph node volume reflect histological stages, i.e. larger lymph nodes are observed in more advanced disease. The mechanism of portal lymphadenopathy in patients with acute and chronic liver disease is unknown. Viral, bacterial infections, and immunological causes are potential etiopathological factors in periportal lympadenopathy. Malignant causes of perihepatic lymphadenopathy have also to be considered.     

Comparison of serum and liver hepatitis C virus quasispecies in HCV-related hepatocellular carcinoma

Background/Aims: The hepatitis C virus (HCV) genome consists of quasispecies populations of heterogeneous variants, especially in the hypervariable region. To assess the profiles of viral quasispecies in HCV-related hepatocellular carcinoma, we studied the viral population patterns in serum and liver tissues of 13 HCV-positive patients with hepatocellular carcinoma developed on cirrhotic and non-cirrhotic livers (5 and 8 cases, respectively).Methods: HCV genome heterogeneity was analyzed by polymerase chain reaction-mediated single-strand conformation polymorphism analysis, which showed multiple DNA bands representing different hypervariable region sequences.Results: The HCV populations were different between tumorous and nontumorous tissues in hepatocellular carcinomas with cirrhosis and in without cirrhosis. At least one or more than one common band was detected in both compartments in all but one case. No significant differences in the complexity of HCV quasispecies were found in hepatocellular carcinoma with or without underlying cirrhosis. Comparison of the HCV quasispecies profiles in serum and liver tissues showed a different distribution of HCV variants between these two compartments in patients. In four cases, both common and compartmentalized sequences were detected, whereas in two cases, both without cirrhosis, the HCV population in serum was completely different from that found in the liver.Conclusions: These results suggest that the complexity of HCV populations is influenced by the presence of hepatocellular carcinoma rather than by the severity of the underlying chronic liver disease. The different quasispecies patterns found in serum and liver may reflect different biological properties of circulating and intrahepatic HCV particles or the existence of extrahepatic sites of replication.     

Clearance of hepatitis C viremia associated with cellular immunity in the absence of seroconversion in the hepatitis C incidence and transmission in prisons study cohort

Understanding the earliest virological and immunological events in acute hepatitis C virus (HCV) infection may provide insight into the determinants of protective immunity. Four cases of HCV viremia with subsequent viral clearance, but without biochemical hepatitis or anti-HCV seroconversion, are reported from a prospective cohort study of prison inmates. Two of the subjects who developed sustained viremia were assessed for production of interferon (IFN)- gamma, by use of the enzyme-linked immunospot (ELISPOT) method and by assessment of HCV cytotoxic T lymphocyte (CTL) activity, CD4 lymphocyte proliferative responses, HCV load, and genotype. After 2-6 months of viremia, all 4 subjects cleared serum HCV RNA. Specific cellular responses were detected in both of the subjects who were assessed, and production of IFN- gamma was demonstrated in one subject. All subjects had weak, but consistent, serological reactivity against HCV nonstructural proteins on immunoblot testing, despite repeatedly nonreactive HCV ELISA tests. These cases highlight the potential for cellular immune responses against HCV to facilitate viral clearance, responses that may model those required for effective HCV vaccination.     

Disappearance of perihepatic lymph node enlargement after hepatitis C viral eradication with direct‐acting antivirals

Perihepatic lymph node enlargement (PLNE) which has been shown to be negatively associated with hepatocellular carcinoma (HCC) occurrence is frequently observed in chronic liver disease; however, changes in the state of perihepatic lymph nodes after eradication of hepatitis C virus (HCV) have not been investigated yet. We aimed to evaluate this issue. We enrolled 472 patients with chronic HCV infection who achieved viral eradication with direct‐acting antivirals (DAA). We investigated whether the status of perihepatic lymph nodes changed before and after HCV eradication (primary endpoint). We also evaluated the association between PLNE and clinical findings such as liver fibrosis or hepatocellular injury before HCV eradication (secondary endpoint). Perihepatic lymph node enlargement was detected in 164 of 472 (34.7%) patients before DAA treatment. Surprisingly, disappearance of PLNE was observed in 23.8% (39 patients) of all PLNE‐positive patients after eradication of HCV. Disappearance of PLNE was not associated with baseline clinical parameters or changing rates of clinical findings before and after DAA treatment. At baseline, presence of PLNE was significantly associated with a lower serum HCV‐RNA level (P = .03), a higher serum AST level (P = .004) and a higher ALT level (P < .001) after adjustment for sex and age. In conclusion, PLNEs became undetectable after DAA treatment in 23.8% of PLNE‐positive patients. Further study with a longer follow‐up period is needed to clarify the clinical importance of this phenomenon especially in relationship with the risk of HCC development.     

Antiviral CD8-mediated responses in chronic HCV carriers with HBV superinfection

Hepatitis B virus (HBV) superinfection in chronic hepatitis C represents a natural model to investigate whether or not hepatitis C virus (HCV) can influence priming and maturation of antiviral T cells; whether or not HBV superinfection, which is known to determine control of HCV replication, can restore HCV-specific T cell responsiveness; and whether or not cytokines stimulated by HBV infection can contribute to HCV control. To address these issues, the function of CD8 cells specific for HBV and HCV was studied longitudinally in two chronic HCV patients superinfected with HBV. Patients with acute hepatitis B were also examined. Frequency and function of HBV tetramer+ CD8 cells were comparable in patients acutely infected with HBV with or without chronic HCV infection. HBV-specific CD8 cell function was efficiently expressed irrespective of serum HCV-RNA levels. Moreover, fluctuations of HCV viremia at the time of HBV superinfection were not associated with evident changes of CD8 responsiveness to HCV. Finally, no correlation was found between serum levels of interferon alpha, interleukin (IL)-12, IL-10, or IL-18 and control of HCV replication. In conclusion, HCV did not affect the induction of primary and memory HBV-specific CD8 responses. HCV-specific CD8 responses were undetectable when HCV-RNA was negative, showing that inhibition of HCV replication in the setting of a HBV superinfection was not sufficient to induce a restoration of CD8 reactivity against HCV.     

Mediastinal lymphadenopathy: an extrahepatic manifestation of chronic hepatitis C?

Normal and enlarged perihepatic and mediastinal lymph nodes are detectable by ultrasonography. Aim of the present study is to determine the detection rate, size, and correlation of mediastinal and perihepatic lymphadenopathy in patients with chronic hepatitis C, healthy controls, and patients with inflammatory or neoplastic mediastinal lymphadenopathy. The mediastinum and liver hilus of 89 patients with chronic hepatitis C as well as of 34 healthy volunteers and 20 patients with mediastinal lymphadenopathy of different origin with adequate sonographic visualization were screened for the number and size of lymph nodes by high resolution ultrasonography. Lymph nodes were detectable in the mediastinum of 75/89 (84%) patients with chronic hepatitis C and 22/34 (65%) healthy volunteers (total lymph node volume [LNV]: 1.0 +/- 0.8 mL versus 0.3 +/- 0.4 mL, p < 0.001). In all patients with mediastinal lymphadenopathy, the mediastinal lymph node volume was above 15 mL. In patients with chronic hepatitis C a trend could be observed, that patients with larger perihepatic lymph nodes reveal also larger mediastinal lymph nodes. High resolution ultrasonography is able to detect enlarged mediastinal lymph nodes in patients with chronic hepatitis C. Mediastinal lymphadenopathy is considered as an extrahepatic manifestation of chronic hepatitis C. In general, the mediastinal lymph node volume differs in size to patients with lymphadenopathy related to neoplasia or sarcoidosis. The mechanism of lymphadenopathy in the liver hilus and mediastinum in patients with chronic hepatitis C is yet unknown.     

Distribution of markers of hepatitis C virus infection throughout the body

The detection of markers of hepatitis C virus (HCV) infection is complicated by the presence of virus in circulating blood. Consequently, it is necessary to target the negative-strand virus RNA or the nonstructural proteins. This has proved challenging, due to unforeseen difficulties in the specific detection of negative-strand viral RNA. However, recent data suggest that although the liver is the major target organ, the virus may be able to replicate in peripheral blood mononuclear cells, lymph nodes, and pancreas and to a more limited degree in bone marrow cells, thyroid, adrenal glands, and spleen. An analysis of the distribution of virus-infected cells in the liver has proved equally challenging. It is clear from the paucity of data generated by immunoblot and Northern blot hybridization that the level of HCV replication in the liver is very low, and this has necessitated studies to detect the viral RNA and antigens by in situ hybridization and immunohistochemistry, respectively. The results of these studies are quite disparate. Those related to in situ hybridization are nonreproducible and reflect wide disparities in the methodology used by different research workers. The data are often internally inconsistent or are inconsistent with data generated by nucleic acid amplification methods to detect the viral RNA in purified RNA extracts or inconsistent with our current understanding of the virus replication cycle. In contrast, the detection of the viral proteins is more reproducible, and some consensus can be reached. It is clear that frozen sections rather than formalin-fixed paraffin-embedded tissue are preferable. Indeed, it is likely that the use of the latter samples can generate nonspecific positive reactions. Surprisingly, many of the most useful data were derived by the use of polyclonal human antibodies from chronic carriers. HCV proteins were detected in the cytoplasm of infected hepatocytes, often in a punctate granular pattern in some hepatocytes and occasionally in monocytes and other cell types. There is often no correlation between HCV antigen expression and the degree of liver cell injury, although patients with lower levels of antigen expression are more likely to respond to interferon therapy.     

Longitudinal analysis of hepatitis C virus replication and liver fibrosis progression in renal transplant recipients

The pathogenesis of hepatitis C virus (HCV) infection was investigated by analysis of changes in viral and histologic parameters in 36 renal transplant recipients who were infected with HCV before transplantation. Each patient was classified according to development of liver fibrosis as assessed by 2 liver biopsies done 45 and 81 months after transplantation: 13 had progressing liver fibrosis (fibrosers) and 23 did not (nonfibrosers). All developed high-titer posttransplant viremia with a significant increase of 1.2 log RNA copies/mL. There were no significant differences in the increases in serum HCV RNA or genotype distributions in fibrosers and nonfibrosers. The hypervariable region (HVR)-1 of the HCV genome was analyzed by cloning and sequencing 20 clones per sample from 5 fibrosers and 5 nonfibrosers. Comparison of samples revealed that liver fibrosis progression was significantly associated with slower HVR-1 quasispecies diversification, suggesting the selection of more aggressive variants in fibrosers.     

Hepatitis C virus core and nonstructural proteins induce fibrogenic effects in hepatic stellate cells

BACKGROUND & AIMS: The mechanisms by which hepatitis C virus (HCV) induces liver fibrosis are unknown. Hepatocytes secrete HCV proteins, which may interact with hepatic stellate cells (HSCs). Our aims were to investigate whether HCV proteins induce fibrogenic effects on HSCs. METHODS & RESULTS: Human-activated HSCs expressed messenger RNA (mRNA) for the putative HCV receptors CD81, LDL receptor, and C1q receptor as assessed by RT-PCR. Incubation of activated but not quiescent human HSCs with recombinant core and NS3 protein increased intracellular calcium concentration and reactive oxygen species production, as well as stimulated intracellular signaling pathways. Adenoviruses encoding core and nonstructural proteins (NS3-NS5) were used to express HCV proteins in HSCs. Expression of core protein increased cell proliferation in a Ras/ERK and PI3K/AKT dependent manner. In contrast, NS3-NS5 protein expression preferentially induced proinflammatory actions, such as increased chemokine secretion and expression of intercellular cell adhesion molecule type 1 (ICAM-1) through the NF-kappa B and c-Jun N-terminal kinase pathways. These effects were attenuated by antioxidants. Infection of freshly isolated rat HSCs with adenovirus-encoding core protein resulted in accelerated cell activation, as assessed by alpha-smooth muscle actin expression. Moreover, adenovirus-encoding core and NS3-NS5 proteins increased the secretion of bioactive TGF beta 1 and the expression of procollagen alpha1(I) in early cultured rat HSCs, as assessed by ELISA and RNase protection assay, respectively. CONCLUSIONS: HCV core and nonstructural proteins regulate distinct biologic functions in HSCs. A direct interaction between HCV proteins and HSCs may contribute to HCV-induced liver fibrosis.     

Persistent Hepatitis C viremia after acute self-limiting posttransfusion Hepatitis C

Persistent viremia after clinical or subclinical hepatitis C virus (HCV) infection is believed to occur in patients with chronic hepatitis C, but little is known about the duration of HCV replication in patients with acute hepatitis who have recovered or the relation of HCV viremia with the kinetics of antibodies to HCV (antiHCV). We tested HCV-RNA and anti-HCV in serial serum samples from 41 patients with posttransfusion non-A, non-B hepatitis, followed for an average of 6 years after transfusion. Serum HCV-RNA was measured by nested polymerase chain reaction, which used primers from the 5′ untranslated region of the HCV genome. Anti-HCV were tested with first- and second-generation enzyme-linked immunosorbent assays (ELISA 1 and ELISA 2), and with a second-generation recombinant immunoblot assay. Of the 41 patients, 10 recovered and 31 progressed to chronic liver disease. HCV-RNA was detected in serum before or simultaneously with the onset of hepatitis in all cases, and lasted between 2 and 6 weeks in 5 of the 10 patients who recovered, whereas it persisted for the entire follow-up period in every case with chronic hepatitis and in the remaining 5 patients with self-limiting hepatitis. Anti-HCV were detected with ELISA 2 in the first serum sample, with raised serum transaminases in 57% of patients, but in only 6% with ELISA 1. In the sample obtained 1 month after the onset of hepatitis, anti-HCV were detected with ELISA 2 in 94% of patients, but in 34% with the ELISA 1. Anti-HCV (anti C-33 and anti-c22) were cleared in the five patients with transient hepatitis C viremia, but remained detectable in those with chronic viremia. In conclusion, serum HCV-RNA is detected at the onset of acute posttransfusion hepatitis C and persists in patients progressing to chronic hepatitis. Some patients with self-limiting hepatitis become HCV-RNA negative soon after the onset of hepatitis, whereas in others it persists throughout follow-up, suggesting the development of a silent carrier state.     

Reciprocal effects of micro-RNA-122 on expression of heme oxygenase-1 and hepatitis C virus genes in human hepatocytes

BACKGROUND & AIMS: Heme oxygenase-1 (HO-1) is an antioxidant defense and key cytoprotective enzyme, which is repressed by Bach1. Micro-RNA-122 (miR-122) is specifically expressed and highly abundant in human liver and required for replication of hepatitis C virus (HCV) RNA. This study was to assess whether a specific miR-122 antagomir down-regulates HCV protein replication and up-regulates HO-1. METHODS: We transfected antagomir of miR-122, 2'-O-methyl-mimic miR-122, or nonspecific control antagomir, into wild-type (WT) Huh-7 cells or Huh-7 stably replicating HCV subgenomic protein core through nonstructural protein 3 of HCV (NS3) (CNS3 replicon cells) or NS3-5B (9-13 replicon cells). RESULTS: Antagomir of miR-122 reduced the abundance of HCV RNA by 64% in CNS3 and by 84% in 9-13 cells. Transfection with 2'-O-methlyl-mimic miR-122 increased HCV levels up to 2.5-fold. Antagomir of miR-122 also decreased Bach1 and increased HO-1 mRNA levels in CNS3, 9-13, and WT Huh-7 cells. Increasing HO-1 by silencing Bach1 with 50 nmol/L Bach1-short interfering RNA or by treatment with 5 mumol/L cobalt protoporphyrin or heme (known inducers of HO-1) decreased HCV RNA and protein by 50% in HCV replicon cells. CONCLUSIONS: Down-regulation of HCV replication using an antagomir targeted to miR-122 is effective, specific, and selective. Increasing HO-1, by silencing the Bach1 gene or by treatment with cobalt protoporphyrin or heme, decreases HCV replication. Thus, miR-122 plays an important role in the regulation of HCV replication and HO-1/Bach1 expression in hepatocytes. Down-regulation of miR-122 and up-regulation of HO-1 may be new strategies for anti-HCV intervention and cytoprotection.     

Sonographic detection of perihepatic lymphadenopathy is an indicator for primary sclerosing cholangitis in patients with inflammatory bowel disease

Aim Primary sclerosing cholangitis (PSC) is a frequent complication in patients with inflammatory bowel disease (IBD). While hyperplasia of the perihepatic lymph nodes has been described in patients with PSC, its prevalence and cause in IBD patients remains obscure. In the present study we address the question of whether ultrasound (US) examination is useful to detect perihepatic lymphadenopathy and improve the diagnostic accuracy for PSC in patients with underlying IBD.Methods A total of 310 consecutive IBD patients were prospectively evaluated by US for enlarged perihepatic lymph nodes, as well as serologic testing for cholestasis-indicating enzymes. In patients with positive test results, viral or autoimmune liver disorders were excluded by serum testing. Next, the presence of PSC was confirmed/excluded by endoscopic retrograde cholangiography (ERC).Results Perihepatic lymphadenopathy was detected by US in 27 of 310 (9%) patients. In 9 (33%) of those, serologic testing identified an underlying autoimmune or viral hepatitis. In the remaining 18 patients, ERC confirmed PSC in 17 (94%) and excluded it in 1. Elevated cholestasis parameters were found in 43 of 310 (14%) patients and 5 (12%) of those were diagnosed with autoimmune or viral hepatitis. In the remaining 38 patients, ERC confirmed PSC in 15 (39%) and excluded it in 23 (61%). Therefore, when autoimmune or viral hepatitis was excluded, enlarged lymph nodes in US predicted PSC more accurately than conventional serum parameters alone (PPV 94 and 39%, respectively [ P<0.001]), and the sensitivity ratio increased by a factor of 1.13 in favor of the US examination.Conclusion In patients with IBD, detection of enlarged perihepatic lymph nodes is a highly predictive indicator for the presence of PSC. Alternative causes of perihepatic lymphadenopathy have to be excluded.     

The presence of an intrahepatic cytotoxic T lymphocyte response is associated with low viral load in patients with chronic hepatitis C virus infection

BACKGROUND/AIMS: The role of cytotoxic T lymphocytes (CTL) in limiting viral replication and producing hepatocellular injury in patients with chronic hepatitis C virus (HCV) infection is controversial. METHODS: Intrahepatic and peripheral blood HCV-specific CTL activity against the entire HCV polyprotein was assessed in 26 patients. CTL responses were assessed after effector lymphocytes were re-stimulated for 6 days in vitro using HCV-vaccinia virus-infected autologous cells expressing HCV antigens. Serum and hepatic viral loads were measured and immunohistochemistry for CD3 and CD8 was performed to localise and enumerate effector cells in liver. RESULTS: A positive CTL response was detected in 39/52 (75%) of assays conducted with intrahepatic mononuclear cells and 21/52 (40%) of peripheral blood assays (P<0.001). The presence of an intrahepatic CTL response was associated with low hepatic viral load (P=0.004). Hepatic lobular infiltration by CD8(+)T cells correlated weakly with serum alanine aminotransferase levels (r=0.42, P=0.04) and no relationship was demonstrated between CTL activity and histological evidence of liver damage. CONCLUSIONS: HCV-specific CTL activity is found more commonly in liver than in blood. An inverse relationship between CTL responses and viral load supports the hypothesis that HCV-specific CTL limit viral replication in patients with chronic HCV infection.     

CD4+ T cell-dependent reduction in hepatitis C virus-specific humoral immune responses after HIV infection

BACKGROUND: Human immunodeficiency virus (HIV) infection adversely affects all stages of hepatitis C virus (HCV) infection, leading to increased rates of viral persistence, higher levels of HCV viremia, and accelerated progression of HCV-related liver disease. These disease interactions may result in part from impairment of B cell function, which is CD4(+) T cell dependent. METHODS: To determine the effect of HIV infection on B cell function, we compared HCV antibody levels and specificities in 29 HCV-infected persons before and after they acquired HIV and assessed the temporal correlation of these changes with overall CD4(+) T lymphocyte counts. RESULTS: The pre-HIV infection HCV antibody titer was a predictor of the subsequent titer for all antigens, and decreasing CD4(+) T cell numbers was strongly associated with a decrease in anti-HCV titers for several antigens. CD4(+) T cells counts of <500 cells/mm(3) were significantly associated with lower HCV antibody end-point titers. Higher HCV end-point titers were associated with fewer years from HIV infection and, for Core antigen, current drug use. CONCLUSIONS: HCV-specific antibody production is impaired by HIV infection, and loss of antibody production depends on CD4(+) T cell depletion. However, the decrease in titers is less significant in those who continue to actively inject drugs.     

Chronic ethanol consumption impairs cellular immune responses against HCV NS5 protein due to dendritic cell dysfunction

BACKGROUND & AIMS: Alcoholic patients with and without chronic liver disease have a high incidence of infection with hepatitis C virus (HCV). Long-term ethanol consumption in mice has been associated with a strikingly reduced CD8(+) cytotoxic T-lymphocyte (CTL) response to HCV nonstructural proteins following DNA-based immunization. This study evaluated the effect of ethanol on dendritic cells (DCs) as a mechanism(s) for reduced CTL activity. METHODS: Mice were fed an ethanol-containing or isocaloric pair-fed control diet for 8 weeks, followed by DC isolation from the spleen. DCs were evaluated with respect to endocytosis properties, cell surface markers, allostimulatory activity, and cytokine production following stimulation. Immune responses to HCV NS5 protein were generated by genetic immunization. Syngeneic transfer was used to determine if DC dysfunction contributed to abnormal cellular immune responses. RESULTS: Long-term ethanol exposure resulted in a reduced number of splenic DCs but did not alter endocytosis capacity. There was an increase in the myeloid and a reduction in the lymphoid DC population. Ethanol reduced expression of CD40 and CD86 costimulatory molecules on resting DCs, which was corrected following stimulation with lipopolysaccharide or poly I:C. There was impaired allostimulatory activity. Cytokine profiles of DCs isolated from ethanol-fed mice were characterized by enhanced interleukin (IL)-1beta and IL-10 and decreased tumor necrosis factor alpha, IL-12, interferon gamma, and IL-6 secretion. Impaired CTL responses to NS5 were corrected by syngeneic transfer of control DCs. CONCLUSIONS: Altered DC function is one of the major changes induced by long-term ethanol consumption, which subsequently impairs the cellular immune response necessary for viral clearance.     

Extrahepatic manifestations in transgenic mice of osteopontin in hepatocytes-A clue to advent of pathological state in various organs of chronic hepatitis C patients.

Osteopontin is a cytokine essential for initiation of Th1 immune reaction. We established transgenic mice expressing osteopontin in hepatocyte, in which liver necrosis with lymphocyte infiltration developed gradually from 12 weeks of age with up-regulated osteopontin levels in the circulation, suggesting that extrahepatic manifestations might also occur as a result of excessive Th1 immune reaction. We examined histological and immunohistochemical features of various organs in these mice. Splenomegaly and enlargement of lymph nodes around the liver and intestine became apparent with marked infiltration of small lymphocytes in the transgenic mice later than 24 weeks of age. Immunostaining revealed that lymphocytes in the spleen and lymph nodes were positive for either CD3 or CD20, suggesting that the infiltrating lymphocytes were both B and T cells. Similar lymphocyte infiltration was found in the lung, kidney and submandibular gland. Alveolar septa became hypertrophic with lymphocyte infiltration, and the lung showed the appearance of interstitial pneumonia. These lesions are similar to extrahepatic manifestations in chronic hepatitis C patients, suggesting that augmented Th1 immune reaction to hepatitis C virus (HCV) proteins or the proteins with molecular mimicry of HCV may be a contributing factor for the formation of the pathological state not only in the liver but also in various organs under chronic infection of hepatitis C virus.