Quantitative analysis of wild-type and HBeAg minus hepatitis B viruses by a sequence-dependent primer extension assay

The ratio between wild-type hepatitis B virus (HBV) and HBV mutant, unable to secrete "e" antigen (HBeAg minus HBV) appears to be an important determinant of the outcome of chronic hepatitis B. Quantitative analysis of wild-type and HBeAg minus HBVs in the blood could be useful to monitor chronic hepatitis B patients. We developed a solid-phase minisequencing assay for both viruses using a primer-guided incorporation of a single labeled nucleotide on an affinity captured biotinylated amplified HBV-DNA template. A standard curve was constructed by mixing increasing quantities of wild type and mutant virus DNAs. The detection of wild-type and HBeAg minus sequences, ranging from 10% to 90% of overall viremia, was linear and reproducible till 0.1 pg/microliter of serum HBV-DNA. The assay yields numerical values and the ratio of incorporated nucleotides defines the relative proportions (%) of the two viral sequences with accuracy. We tested the sensitivity and accuracy of the minisequencing on mixed end point dilutions of wild-type and HBeAg minus reference sera and amplified products. The feasibility and reproducibility of the assay were tested in 35 sera from 21 HBsAg positive patients with chronic hepatitis B using both minisequencing and oligo-hybridization assays. A high correlation was found between the two assays (r = 0.957 P < 0.0001). In conclusion, the minisequencing assay provides a precise and reproducible quantitative analysis of wild-type and HBeAg minus HBVs in clinical specimens. It is proposed to study the relations between HBV heterogeneity and the course of hepatitis B and its response to therapy.

Hepatitis C virus infection and liver disease: peculiar epidemiological and clinicopathological features

Hepatitis C virus (HCV) infection is associated with a wide spectrum of liver disease ranging from asymptomatic carriage to severe forms of chronic hepatitis. HCV is not invariably pathogenic and genetic heterogeneity of HCV could be a major cause of such a variability. In clinical practice this means that presence and replication of the virus do not invariably imply a virus-induced liver damage. IgM antibodies that are the best diagnostic tools for the other forms of viral hepatitis are not sensitive and specific enough for hepatitis C, therefore we have to look for alternatives. Detection of anti-HCV does not help to distinguish past from present infections and only anti-HCV seroconversion in previously negative patients can indicate a recent HCV infection. However, the significant association between serum anti-C100-3 and HCV-RNA suggests that anti-HCV can be considered an indirect marker of HCV infectivity. In anti-HCV-negative infections and early acute hepatitis cases HCV-RNA detection will represent a valid diagnostic alternative. In patients undergoing antiviral therapy monitoring anti-HCV by immunoblotting assays and HCV-RNA by quantitative assays represent a valid tool to predict response that invariably has occurred in patients who had undetectable serum HCV-RNA and/or decreasing anti-HCV titres. Assays that detect multiple anti-HCV antibodies all together appear unsuitable for monitoring because they miss the disappearance of single antibodies. Anti-C22 appears the most frequent and earliest to be detected and usually it has the highest titre. Anti-C100 titres decrease earlier than anti-C33 and anti-C22 in patients with chronic HCV hepatitis who respond to antiviral therapy. The natural course of HCV infection appears to be characterized by three consecutive phases: disease, asymptomatic carrier and recovery. If transition from the first to the last occurs very slowly or the disease phase persists for years it may warrant in susceptible hosts severe forms of liver disease.

Intramuscular natural beta interferon in the treatment of chronic hepatitis B: a multicentre trial. Italian Hepatitis B Study Group

A randomized controlled multicentre trial was undertaken to assess the effectiveness of natural IFN beta (Frone) administered by intramuscular injection to chronic hepatitis B patients. Sixty-five HBsAg and HBeAg carriers with chronic hepatitis and intrahepatic HBcAg histologically proven by immunohistochemistry were included in the study. Fifty-nine patients completed the study: 30 of them (mean age 27 years, range 14-55 years, 16M/14F) were treated with 5 Million Units (MU)/m2 of Frone three times weekly for six months and 29 (mean age 28 years, range 14-59 years, 18M/11F) were not treated. The 2 groups of patients were similar in their clinical and histological (CAH/CPH ratio 25/5 and 20/9) characteristics. In the treated patients, a significant reduction in viremia was observed starting from the 6th month of the follow-up (p < 0.01), accompanied by a significant reduction of serum aminotransferase levels (p < 0.005). At the end of therapy serum HBeAg was undetectable in 7 of 30 (23%) treated patients and in 1 of 29 (3%) controls. Six months after the end of treatment 8 of 30 (26%) treated patients and 5 of 29 (17%) controls were HBeAg negative. A significant difference (p < 0.05) was observed in the rate of anti-HBe seroconversion between the 2 groups starting from the 8th month of follow-up. Mild side effects, namely fever < 38 degrees C and asthenia were observed in 20% and 37% of treated patients. In conclusion natural beta interferon given intramuscularly is effective in HBeAg positive patients suffering from chronic hepatitis B with optimal compliance.(ABSTRACT TRUNCATED AT 250 WORDS)

Ribavirin treatment for chronic hepatitis D: a pilot study

To assess whether therapy with Ribavirin may affect the course of chronic delta hepatitis, nine Italian patients with this disease received the drug orally at a dosage of 15 mg/kg daily for 16 weeks. At the end of the therapy period, all patients were followed for 12 additional months. Seven patients completed the trial. Two patients were withdrawn: one developed hemolytic anemia, and the other intractable itching. At the end of treatment HD viremia was reduced in one patient, had cleared in another, and was unchanged in the remaining five patients. None of the patients decreased their alanine transferase (ALT) levels by more than 50%. At the doses given in this study. Ribavirin did not show significant antiviral effects in chronic hepatitis D, and was not effective in reducing the biochemical markers of liver inflammation and necrosis.

Albumin gene expression in liver tumors: diagnostic interest in fine needle aspiration biopsies

Albumin is a specific product of normal and transformed hepatocytes, but unfortunately its immunohistochemical demonstration proves unreliable because of diffusion artifacts. An in situ hybridization procedure to reveal albumin mRNA was applied to fine needle aspiration specimens of liver nodes with the aim of testing the usefulness of this marker in the cytological diagnosis of hepatocellular carcinomas (HCC). A 51-base pair oligonucleotide probe was labeled with digoxigenin and used on paraffin sections of alcohol-fixed cell blocks. A series of 97 cases originally interpreted, on the basis of cytology alone, as "hepatocellular carcinoma" (62 cases), as "carcinoma cells, not otherwise specified" (15 cases), as "adeno-carcinoma" (16 cases), and as "non-epithelial neoplastic cells" (4 cases), was studied. In all cases, clinical and follow-up information was obtained; a diagnosis of HCC was reached with certainty in 44 cases and suspected in 22. Thirty-one other cases were proven to be bile duct adenocarcinomas or metastatic tumors. Taking into account proven cases only, albumin mRNA was found in 42/44 HCC and in none of the control cases (sensitivity, 95.5%; specificity, 100%). Of 22 cytologically suspected HCC, albumin mRNA was positive in 19 cases. Also, high grade pleomorphic HCCs expressed albumin gene, and this finding is of value in the differential diagnosis with liver metastases of anaplastic tumors from lung, adrenal, pancreas, etc. The diagnosis of HCC on a cytological basis is becoming increasingly important because most cases are unresectable and have to be included in different therapeutic protocols.(ABSTRACT TRUNCATED AT 250 WORDS)

Hemodynamic, hemorheologic, and hemocoagulative changes after treatment with picotamide in patients affected by peripheral arterial disease (PAD) of the lower limbs

Effects of picotamide on platelet activity and on some hemorheologic, coagulative, and hemodynamic parameters were investigated in a randomized, double-blind, placebo-controlled study for eighteen months. Twenty patients, average age 61.5 +/- 9.6 (SD) years, with peripheral arterial disease (PAD) at functional stage 2 of the Fontaine classification and with intermittent claudication for at least six months were studied. Ten patients received tablets of picotamide, 300 mg three times a day, and 10 subjects received three identical placebo tablets each day. Similar atherosclerotic disease risk factors were present in both groups. Picotamide induced a significant decrease of plasma viscosity, fibrinogen, and beta-thromboglobulin and an increase of amplitude of the photoplethysmographic wave.

Detection of hepatitis C virus RNA by reverse-transcriptase and polymerase chain reaction: clinical applications of quantitative analysis

Polymerase chain reaction (PCR) applications to diagnostics allowed the detection of viral nucleic acids in expected and unexpected clinical circumstances. This has raised some scepticism on the practical usefulness of PCR in the routine laboratory and emphasized the need for quantitative analysis. We addressed this question detecting HCV-RNA by a single step RT-PCR in serum samples from 50 patients with chronic non-A, non-B hepatitis included in clinical trials for recombinant alpha-interferon therapy. We obtained at least 5 serum specimens from each patient (baseline, during and after therapy samples) during an 18-month mean follow-up (range 12-45 months). RT-PCR was performed on total RNA extracted from 100 microl serum aliquots using primers for the highly conserved 5'NCR of HCV-RNA and 35 amplification cycles. PCR products were analyzed by agarose gel electrophoresis and Southern blot hybridization against a P(32)-oligonucleotide probe. Sensitivity was evaluated in separate experiments on tenfold dilutions of a reference Chimp serum containing 10(6) CID(50)/ml. The overall sensitivity of our assay ranged between 10(2) and 10(3) genome Eq./ml. We establish a semiquantitative score system to evaluate viremia levels: 2 = HCV-RNA levels >10(4) genome Eq./ml; 1 = levels between 10(3) and 10(4) g.Eq./ml; 0 = levels less than 10(2) g.Eq/ml. The reproducibility of this scoring system was confirmed testing repeatedly in duplicate end-point dilutions of positive serum samples. A statistically significant relation was observed between elevated HCV-RNA and ALT values (83.8%, chi-square 159.963 P < 0.001). Response to IFN therapy was significantly better in patients with lower baseline HCV-RNA levels. A time relation was found between flare-ups of serum HCV-RNA levels and ALT elevations higher than 3 x normal values viremia elevations coincident or occurring about 1 month earlier than ALT elevations. This finding suggests that immuno pathogenesis might be responsible of HCV-induced liver damage as in chronic hepatitis B where identical relations were observed between viremia and ALT serum levels. In conclusion, single-step HCV-RNA RT-PCR can be a specific and reproducible semiquantitative assay and provides useful diagnostic informations for therapeutic decision making and monitoring of HCV-infected patients.

Monitoring the natural course and response to therapy of chronic hepatitis B with an automated semi-quantitative assay for IgM anti-HBc

The clinical significance of a semi-quantitative microparticle enzyme immunoassay (IMx Core-M, Abbott) was evaluated for detection of IgM-class antibodies against the hepatitis B core antigen (IgM anti-HBc) in 136 hepatitis B surface antigen (HBsAg) positive individuals (96 chronic HBV carriers, 20 patients with chronic HBV-HDV infections and 20 patients with acute hepatitis B) and 50 HBV-negative controls. Baseline and follow-up sera (4-11 samples) were analysed from 79 carriers with chronic hepatitis B, 44 of whom were treated with interferon. IMx indexes above 3,000 were found in 95% of the acute hepatitis B patients and above 0.300 in 91.5% of patients with ongoing chronic hepatitis B. IMx indexes between 0.200 and 0.300 were observed in (a) patients with recent HBeAg to anti-HBe seronconversion (6-12 months) and normal serum ALT levels, (b) patients immuno-tolerant to HBV infection and without liver disease despite high levels of viremia, and (c) patients with anti-HBe-positive chronic hepatitis B during 7-13-month intervals of asymptomatic carriage between episodes of disease reactivation. IMx indexes below 0.200 were detected in all HBV-negative individuals and healthy HBV carriers, in 14 (70%) of 20 chronic hepatitis D patients and in all but 1 of 22 interferon-treated patients with histological remission of liver disease, 5-12 months after clearance of viremia and normalization of serum ALT levels. In contrast, IMx indexes remained above 0.200 in all patients with hepatitis B reactivation.(ABSTRACT TRUNCATED AT 250 WORDS)

Is high AgNOR quantity in hepatocytes associated with increased risk of hepatocellular carcinoma in chronic liver disease?

AIMS

To evaluate whether high numbers of silver staining nucleolar organiser regions (AgNORs) in hepatocytes are associated with increased risk of hepatocellular carcinoma in chronic liver disease.

METHODS

The quantitative distribution of AgNORs was studied in the liver biopsy specimens of 33 patients with chronic liver disease, 11 of whom developed hepatocellular carcinoma. The interval between liver biopsy and diagnosis of hepatocellular carcinoma was 26 months (range one to 61 months); the mean follow up of patients without hepatocellular carcinoma was 45 months (range 24-59 months). Quantitative evaluation of AgNORs was carried out on silver stained routine sections by morphometric analysis, using a computer assisted image analysis system.

RESULTS

High interphase AgNOR values (> 3 microns2) were found in hepatocytes of nine out of the 11 (82%) patients in whom neoplastic transformation occurred. Of the remaining 22 patients, only seven (31%) had AgNOR values higher than > 3 microns2 (chi 2 4.83; p = 0.036).

CONCLUSIONS

These results indicate that high numbers of interphase AgNORs are associated with increased risk of hepatocellular carcinoma in patients with chronic liver disease.

Colon cancer seeding after percutaneous fine needle aspiration of liver metastasis

Fine needle aspiration or biopsy is used for cytologic diagnosis of many intra-abdominal tumors including focal liver lesions. The incidence of needle tract seeding is quite low. In this paper the first case of cutaneous seeding after percutaneous fine needle aspiration of liver metastasis is reported in a case of colon cancer. We suggest using this method for cytologic diagnosis in hepatic tumors when surgical resection is not possible and when patients will be treated with invasive therapies and to avoid fine needle aspiration biopsy in patients undergoing surgical resection or when there is a confident diagnosis of HCC by non-invasive procedures.

[The temporary work incapacities of professional administrative workers and nurses]

We show the results of a retrospective study designed to assess the features of transient job disability (TJD) episodes of workers from two groups (clerks and nurses) from an urban health basic zone with 24,536 inhabitants, out of which 6,009 were active workers registered in social security databases. Population pyramid and job distribution in active workers were obtained from a random sample including 5% of the active population, out of which 17% were clerks and 5.54% nurses. There were 1098 TJD episodes in 1990; 32.4% of them involved clerks and 8.3% nurses. The mean length of episodes was 28.2 days in nurses and 27.8 days among clerks, compared to 32.4 days in the active population. These differences remained (p < 0.001) even after excluding TJD episodes of pregnant women, in whose case the mean length of episodes involving male or female workers was the same. The percentage of TJD episodes was higher among female nurses and clerks, than among the whole female population. Influenza was responsible for 20.5% of TJD in clerks against 14.3% among nurses and 14.8% in the whole active population. We conclude that, in the groups studied, the rate of job absenteeism was higher than in the whole population, and higher in female than in males. However, in the whole population, there were no differences in TJD rates between males and females. We discuss that several factors other than illness may explain the differences among groups.

Compartmentalization of T lymphocytes to the site of disease: intrahepatic CD4+ T cells specific for the protein NS4 of hepatitis C virus in patients with chronic hepatitis C

The adult liver is an organ without constitutive lymphoid components. Therefore, any intrahepatic T cell found in chronic hepatitis should have migrated to the liver after infection and inflammation. Because of the little information available on the differences between intrahepatic and peripheral T cells, we used recombinant proteins of the hepatitis C virus (HCV) to establish specific T cell lines and clones from liver biopsies of patients with chronic hepatitis C and compared them with those present in peripheral blood mononuclear cells (PBMC). We found that the protein nonstructural 4 (NS4) was able to stimulate CD4+ T cells isolated from liver biopsies, whereas with all the other HCV proteins we consistently failed to establish liver-derived T cell lines from 16 biopsies. We then compared NS4-specific T cell clones obtained on the same day from PBMC and liver of the same patient. We found that the 22 PBMC-derived T cell clones represent, at least, six distinct clonal populations that differ in major histocompatibility complex restriction and response to superantigens, whereas the 27 liver-derived T cell clones appear all identical, as further confirmed by cloning and sequencing of the T cell receptor (TCR) variable and hypervariable regions. Remarkably, none of the PBMC-derived clones has a TCR identical to the liver-derived clone, and even with polymerase chain reaction oligotyping we did not find the liver-derived clonotypic TCR transcript in the PBMC, indicating a preferential intrahepatic localization of these T cells. Functionally, the liver-derived T cells provided help for polyclonal immunoglobulin (Ig)A production by B cells in vitro that is 10-fold more effective than that provided by the PBMC-derived clones, whereas there is no difference in the help provided for IgM and IgG production. Altogether these results demonstrate that the protein NS4 is highly immunogenic for intrahepatic CD4+ T cells primed by HCV in vivo, and that there can be compartmentalization of some NS4-specific CD4+ T cells to the liver of patients with chronic hepatitis C.

Propafenone-induced liver injury: report of a case and review of the literature

A case of an acute cholestatic syndrome associated with use of the antiarrhythmic drug propafenone is reported here. The close time relationship between the administration of the drug and the acute onset of the liver damage, the histological findings, and the reappearance of biochemical signs of liver dysfunction upon rechallenge with the same medication strongly suggest that propafenone was involved in the pathogenesis of this syndrome. Although rare, hepatotoxicity from this widely used antiarrhythmic medication should be kept in mind in the differential diagnosis of sudden cholestatic syndrome of obscure origin.

Infectious hepatitis B virus variant defective in pre-S2 protein expression in a chronic carrier

All human hepatitis B viruses characterized so far express three envelope proteins, pre-S1, pre-S2, and HBs, which are believed to function as binding proteins for the cellular receptor, as targets for immune-mediated virus elimination, and in virion morphogenesis and secretion. Here we report the characterization of infectious HBV variant genomes that are unable to express a pre-S2 protein and which were derived from serum of a highly viremic chronic carrier. Direct sequencing of the amplified pre-S region and sequencing of 50 cloned amplified pre-S DNA fragments revealed that in all molecules, in addition to numerous nucleotide changes, there were deletions of the pre-S2 translation initiation codon and three codons 54 nucleotides downstream thereof. No pre-S2 protein and altered pre-S1 proteins were found in the serum of the patient. Cloned infectious HBV DNA genomes having the pre-S region substituted by the variant pre-S region were replication competent in cultured hepatoblastoma cells. Morphologically normal virions were efficiently secreted and were infectious for primary human hepatocyte cultures. These data demonstrate that HBV devoid of pre-S2 protein can occur in vivo as a dominant or exclusive virus population and that expression of the pre-S2 protein is not essential for HBV replication, virion morphogenesis, secretion, or in vitro infectivity.

[Influence of sex, age, and profession on transient work disability at a health center]

OBJECTIVE

To analyse whether the variables of gender, age and type of job of those in full-time work affect short-term unfitness for work (SUW) in a study undertaken within our health area.

DESIGN

A prospective and retrospective study of all the SUW.

SETTING

Primary Care. An urban Health Centre.

PARTICIPANTS

Those people with full-time jobs registered at the Centre.

MAIN MEASUREMENTS AND RESULTS

The entire 1098 certificates of SUW issued in 1990 were processed. The population pyramid and job distribution among those in full-time work was obtained by a random sample of 5% of the active population. When time off for maternity (TOM) was excluded, women accounted for 44.8% of SUW and men 55.2%. There were no significant differences with the percentages these figures represent for the active population as a whole. The number of SUW per 100 people in work was 15.9 for men and 21.5 and 17.4 for women (including and excluding TOM, respectively). The average length of SUW, excluding maternity, was 27.06 days for men and 26.8 for women. On the question of age, those under 19 and over 40 contributed least to the SUW percentage. Additionally, those under 19 and over 60 were the proportions of the population least prone to SUW. On the question of type of job, we found a higher contribution to absenteeism than expected within Groups 3 and 4 and less in Groups 0/1, 5 and 7/8/9. The longest average length of time for SUW was in Group X (84.2 days/SUW).

CONCLUSIONS

Excluding TOM, gender does not appear to be a variable that affects SUW. Age group and type of job are variables affecting SUW. It will be necessary to undertake research into whether there are additional social or labour factors which might explain.

Hepatitis B virus heterogeneity, one of many factors influencing the severity of hepatitis B

The pathogenesis of hepatitis B can be subdivided into three sequentially correlated events: (a) loss of virus tolerance, (b) liver cell necrosis mediated by virus specific inflammatory response, (c) non-specific death of functionally compromised hepatocytes mediated by inflammatory cytochines released by virus specific inflammatory response. The severity of liver damage depends on the occurrence of these events as well as other factors. The HBeAg defective mutant appears to be involved in the loss of virus tolerance and therefore in the pathogenesis of acute hepatitis B. In addition it is positively selected by antiviral immunoreaction, behaves as an escape mutant, and it also contributes to the pathogenesis of chronic hepatitis B. The combination of these characteristics explains the relative prevalence of this mutant over wild-type HBV in patients with severe acute hepatitis B and in chronic HBsAg carriers during anti-HBe seroconversion and/or hepatitis B exacerbations. However, the absence of HBeAg defective mutants in some cases of severe and fulminant hepatitis B as well as its detection in asymptomatic carriers of HBsAg should not be surprising. The severity of hepatitis is influenced by many other factors: the number of virus infected cells, the competence and genetic heterogeneity of the immune system, the vigor and extent of non-specific inflammatory response and the killing of hepatocytes endangered by other diseases or infected with other hepatotropic viruses.

T-lymphocyte response to hepatitis C virus in different clinical courses of infection

BACKGROUND

To assess the role played by the immune response in the outcome of hepatitis C virus infection, the CD4+ T-lymphocyte response to viral antigens was studied in infected individuals with different clinical courses.

METHODS

Using six recombinant proteins of hepatitis C virus, the study assessed the proliferative responses of peripheral blood mononuclear cells from 41 patients with chronic hepatitis C, 11 patients whose chronic hepatitis was successfully treated with interferon alfa and 11 healthy HCV seropositive individuals.

RESULTS

(1) Sixty-five percent of hepatitis C virus-seropositive individuals had CD4+ T-cell responses to viral proteins. (2) All viral proteins were immunogenic for T cells, although NS4 was the most immunogenic. (3) There was a significant correlation between the presence of CD4+ T cell responses to Core and a benign course of infection in healthy seropositives, most of whom were viremic.

CONCLUSIONS

CD4+ T-cell responses to Core, although they do not coincide with virus clearance, are associated with a benign course of infection and may be required to maintain humoral and cellular responses protective against the disease.

Hepatitis C virus infection in type II essential mixed cryoglobulinemias

The possible relationship between essential mixed cryoglobulinemias (EMCs) and hepatitis C virus (HCV) has been investigated in eight patients with type II EMCs and biochemical signs of liver damage, whose serum tested positive in the ELISA for anti-HCV. Sera were tested using the 2nd generation RIBA assay, while serum HCV-RNA was measured semiquantitatively by a RT-PCR in whole serum, cryoprecipitates and supernatants. In all patients a percutaneous liver biopsy and a bone marrow biopsy were performed. At liver biopsy, chronic active hepatitis and/or cirrhosis were present in 6 patients; in the remaining two, a lymphoplasmacytoid infiltration of elements positive for kappa light chains was found. In all patients a bone marrow biopsy showed a paratrabecular infiltration of monoclonal lymphoplasmacytoid elements similar to those found in the liver of the two patients described above. Antibodies against structural and non-structural HCV proteins were detectable in the serum of all patients. HCV-RNA was amplified from the whole sera, cryoprecipitates and supernatants: significantly higher concentrations were found in cryoprecipitates than in supernatants. Our results confirm the high prevalence of HCV infection and ongoing viral replication in patients with type II EMC and suggest the possible implication of HCV in EMC pathogenesis.

Problems in diagnosing viral hepatitis

The most reliable method of making a specific aetiological diagnosis of chronic viral hepatitis would be to identify virus specific cytotoxic T lymphocytes responsible for the killing of virus infected hepatocytes in each patient's liver. Unfortunately, this can not be proposed for routine diagnosis and surrogate tests are required. The detection of virus markers, and even of the virus itself, does not imply that liver damage is caused by virus infection. Indirect markers of the host's antiviral immunoresponse have to be used to confirm more specifically the diagnosis of viral hepatitis. IgM antibodies against viral antigens implicated in the elimination of the virus seem to be suitable alternative candidates. Significant changes in the serum values of viraemia and aminotransferases occur within a few days, while a significant variation in liver histology takes much longer. Only the kinetics of the highly variable parameters can be used for an appropriate study of the relationship between viraemia, antiviral immunoresponse, and liver cell necrosis. Quantitative and dynamic analyses of hepatitis virus markers seem the most suitable and reliable methods of monitoring the patients eligible for antiviral treatment and identifying the most appropriate time to start this.

Accumulation of a cellular protein bearing c-myc-like antigenicity in hepatic and non-hepatic delta antigen expressing cells

Patients with chronic but not acute hepatitis delta virus infection undergo a strong accumulation of a protein of cellular origin which specifically reacts with a panel of anti-c-myc antibodies and which is expressed in the same nuclei that express the delta antigen. In this paper we report on the in vitro characterization of this phenomenon. The delta antigen induced c-myc antigen accumulation can occur in vitro upon transfection of HBsAg positive and negative cell lines with HDAg expression vectors. Using recombinant vaccinia viruses expressing only p24 or p27 we demonstrate that structures common to the two isoforms of HDAg are responsible for the phenomenon, which is not restricted to cells of hepatic origin.

Hepatitis C virus infection and disease. Diagnostic problems

Hepatitis C virus (HCV) is a lipid-enveloped single-stranded RNA virus with an unknown physical structure as only putative HCV particles have been identified by electron microscopy. Although HCV lacks the retroviral properties of being able to integrate into host DNA, it causes chronic infection in a considerable number of infected individuals (40-60%). Chronic infection is associated with a wide spectrum of liver diseases ranging from normal presentation to the different forms of chronic hepatitis, cirrhosis (about 20% of cases) and hepatocellular carcinoma. HCV therefore is not invariably and equally pathogenic, and genetic heterogeneity could be a major cause of such variability. Diagnosis of HCV infection relies on anti-HCV and HCV-RNA detection. Using second-generation assays, diagnostic sensitivity has increased to about 95%, but detection of anti-HCV does distinguish past from present infections. Only rising anti-HCV titres or anti-HCV seroconversion confirm a recent HCV infection. In anti-HCV-negative infections and cases of early acute hepatitis, HCV-RNA detection by RT-PCR represents a valid diagnostic alternative. In patients undergoing interferon therapy, testing for anti-HCV by immunoblotting represents a valid routine tool to monitor response. Anti-C-22 has the highest titre and persists longer while anti-C-100 is the earliest antibody to disappear in responders. The significant association between serum anti-C-100, HCV-RNA and liver disease suggests that anti-C-100 is an indirect marker of hepatitis C, but true markers of HCV-induced liver disease are still lacking.

Expression of estrogen receptor mRNA in tumorous and non-tumorous liver tissue as detected by in situ hybridization

Estrogen receptor mRNA was detected by a non-radioactive in situ hybridization assay in tumor and non-neoplastic liver tissues. A synthetic oligonucleotide complementary to the human estrogen receptor mRNA was 3'-labeled with digoxigenin-deoxyuridine triphosphate (dUTP). Hybrids were revealed by an alkaline phosphatase-conjugated anti-digoxigenin antibody. Fourteen primary hepatocellular carcinoma tissues (and one metastatic) were obtained at surgery from 15 patients. The corresponding non-neoplastic liver tissues were available in 13 cases. The estrogen receptor mRNA was detected in 11 tumorous and 7 non-tumorous liver specimens. The staining was cytoplasmic and involved the majority of transformed hepatocytes, whereas a less widespread and weaker signal was found in normal hepatocytes. Within non-neoplastic tissue, bile duct epithelial cells could also be occasionally stained, whereas other cell types, such as vasal endothelial cells, were negative. Appropriate controls established the specificity of the reaction. Detection of the estrogen receptor protein by immunohistochemistry in these same specimens was invariably negative. This in situ hybridization assay can therefore be used as a complementary tool to evaluate the estrogen receptor expression within liver cancer.