Humoral antibodies to the capsid antigen of Epstein-Barr virus in Hodgkin's disease.

By the method of indirect immunofluorescence it has been shown in P3HR-I cells that sera from patients with Hodgkin's disease contain high titers of humoral antibodies to the capsid antigen of Epstein-Barr virus (EBV). Higher titers of antibodies of EBV were found in histological variants of Hodgkin's disease with an unfavorable course. The variant of lymphocyte depletion is accomplished by higher titers of the virus and poorer prognosis than the nodular-sclerotic variant having a course with lower titers of antibodies and better prognosis. At the same time, the level of antibodies does not depend on the results of the therapy applied. In the sera of patients with reticulosarcoma or lymphosarcoma no increase in the level of antibodies to EBV has been discovered in comparison with a group of healthy donors; in acute leukemia a certain tendency to decrease in the level of antibodies to this virus can be observed.     

IgM and IgA antibodies generated against hepatitis C virus core antigen in patients with acute and chronic HCV infection

Antibody subclasses directed against the core protein (HCc) of hepatitis C virus (HCV) were measured in 27 patients with acute non-A, non-B (NANB) hepatitis, and 99 patients with chronic HCV-associated liver disease. IgM, IgA, and IgG anti-HCc responses were observed in 11 (40.7%), 7 (25.9%), and 18 (67%) patients with acute NANB hepatitis, respectively. Twenty-four (24.2%) and 40 (40.4%) patients with chronic HCV infection also had detectable IgM and IgA, respectively. IgM anti-HCc inconsistently detected acute infection, and HCV ribonucleic acid (RNA) could be detected preceding the rise in anti-HCc antibodies in five consecutive patients with acute hepatitis. IgM anti-HCc also could not distinguish acute from chronic infection and did not correlate with histologic progression. However, the form of IgA present (polymeric vs monomeric) did discriminate acute from chronic infection and the IgA anti-HCc titer correlated with histologic evidence of liver disease in patients with chronic HCV infection.     

A solid-phase radioimmunoassay for detection of IgM antibodies to hepatitis A virus.

The conditions for a sensitive and specific solid-phase radioimmunoassay (RIA) for the detection of IgM antibodies to hepatitis A virus (HAV) were optimized, and the RIA was used to assay sera from patients with hepatitis. IgM antibodies to HAV reached highest concentrations between one and three weeks after onset of icterus and were measurable in follow-up sera for at least 12 months after infection. To prove the specificity, the IgG antibodies were separated from patient sera by sucrose density-gradient centrifugation. The remaining IgM antibodies, after treatment with beta-mercaptoethanol, did not bind in the RIA, and, when the anti-IgM antibody bound to the solid phase was replaced with anti-IgG, a negative result was obtained with incubation of IgM antibody to HAV. Also, the presence of IgG was shown not to interfere with measurement of IgM antibody to HAV. Finally, as a further specificity control, 50 sera positive for rheumatoid factor or from patients infected with hepatitis B virus, cytomegalic inclusion disease, infectious mononucleosis, influenza A virus, rubella, or measles were tested, and all of these sera were negative for IgM antibody to HAV.     

Coexistence of IgM antihepatitis A virus and IgM antihepatitis E virus in acute viral hepatitis: a prospective, multicentre study in Korea

This study investigated the clinical, serological and molecular characteristics of coexistence of both immunoglobulin M (IgM) antihepatitis A virus (HAV) and IgM antihepatitis E virus (HEV) in acute viral hepatitis using a prospective, multicentre design. Among a total of 771 symptomatic cases with acute viral hepatitis enrolled in a Korean city from September 2006 to August 2008, coexistence of IgM anti-HAV and IgM anti-HEV was found in 43 patients (A+E group; 6%), while the existence of IgM anti-HAV alone was found in 595 patients (A group; 77%) and that of IgM anti-HEV alone in 14 patients (E group; 2%). Clinical data analysis and measurement of IgM and IgG anti-HEV were performed using two different commercial kits, and HAV RNA and HEV RNA were detected in available serum or stool samples. The clinical features of the A+E group were similar to those of the A group. HAV RNA detection rates in the A+E and A group were similar, while HEV RNA was detected only in the stool samples of the E group, not in the A+E group. Comparative testing of anti-HEV using two different ELISA kits showed markedly discordant results for IgM anti-HEV positivity and consistently low positivity for IgG anti-HEV in the A+E group. Coexistence of IgM anti-HEV measured by the Genelabs ELISA kit in the setting of hepatitis A appears to yield false-positive results in nonendemic areas of HEV infection. Diagnosis of hepatitis E using IgM anti-HEV should be made with caution.     

Characteristics of hepatitis B X antigen, antibodies to X antigen, and antibodies to the viral polymerase during hepatitis B virus infection

The characteristics of hepatitis B virus (HBV) X antigen (HBxAg) and antibodies against the X antigen (anti-HBx) and the viral polymerase (anti-pol) were determined in 85 HBV-infected patients. HBxAg was detected in sera positive for HBV e antigen (HBeAg) and HBV DNA in patients with acute and chronic hepatitis, while anti-HBx appeared when markers of viral replication became undetectable. HBxAg was common in the liver among patients with chronic hepatitis independent of HBV replication markers but was closely correlated with elevated alanine aminotransferase, implying that HBxAg in liver may be important in the pathogenesis of chronic infection. Anti-pol was detected in many samples positive for HBeAg and HBV DNA and less often in serum samples without markers of HBV replication, suggesting that this marker could reflect ongoing viral replication in the liver, even though such markers were absent from sera.     

Detection of antibodies against hepatitis B virus polymerase antigen in hepatitis B virus-infected patients

By the use of a truncated recombinant hepatitis B virus polymerase antigen, we have characterized a series of patient sera for anti-hepatitis B virus polymerase antibodies. Seven of 54 (13%) had antipolymerase antibodies detectable by Western blot analysis, and no close correlation was apparent between the disease status and patient's immune response against hepatitis B virus polymerase antigen. Our results indicate that serologic responses to the viral polymerase are demonstrable but suggest that such antibodies are not likely to be clinically useful as diagnostic or prognostic markers of infection.     

Isolated antibodies against the core antigen of hepatitis B virus in HIV-infected patients

The aim of this study was to describe the frequency and significance of isolated antibodies against the hepatitis B virus (HBV) core antigen (HBc) in 2185 HIV-infected patients of the Aquitaine Cohort. Antibodies against HBc were found in 372 subjects (17%). Patients with isolated anti-HBc antibodies were more frequently coinfected with hepatitis C virus (HCV) (58.2%) than those who were anti-HB surface (HBs) antibody positive (22.9%, P<0.001) and those who were dually reactive anti-HBs/anti-HBc antibody positive (27.3%, P<0.001). These results suggest interactions between HBV and HCV. As observed in patients not infected with HIV, the "anti-HBc-alone" serological profile could reflect essentially late immunity with undetectable anti-HBs antibodies. However, an occult HBV infection cannot be ruled out.     

Transient immunoglobulin M antibody response to hepatitis C virus capsid antigen in posttransfusion hepatitis C: putative serological marker for acute viral infection.

The development of serological assays for hepatitis C virus (HCV) has made specific diagnosis possible. However, markers useful in indicating acute-phase HCV infection have not been identified. By an immunoblotting method, we characterized the IgM and IgG antibody response against HCV capsid antigen in patients with HCV infection. Among 88% of patients with acute posttransfusion hepatitis C recruited in a prospective study, there was a transient IgM antibody response. The IgM antibody appeared shortly after onset of hepatitis (average 3.7 weeks), persisted for several months (average 18 weeks), and then disappeared. In contrast, the IgG antibody persisted long-term once it appeared. Among patients with chronic hepatitis C with milder disease activities (serum aminotransferase increase above normal levels of less than 4-fold), the IgM antibody was negative in the majority (72%). In those with acute exacerbations (aminotransferase increase of greater than 10-fold), about 55% were negative for the IgM antibody. The reactivity of the IgM antibody in the rest was weaker or became negative upon further dilution of serum. The results suggest that IgM anti-capsid antibody may serve as a marker indicating acute or active HCV infection.     

Immunoglobulin A antibody against hepatitis B core antigen in the acute and persistent infection with hepatitis B virus

Antibody to hepatitis B core antigen of immunoglobulin A class was determined in the serum of patients infected with hepatitis B virus by a sandwich-type solid-phase radioimmunoassay with monoclonal antibodies. The antibody, as defined by a sample to normal ratio greater than 2.1, was detected in all of 39 patients with acute hepatitis, with titers varying widely depending on the time of blood sampling. In persons with persistent infection, the antibody was detected in only 2 (4%) of 46 asymptomatic carriers of the virus, contrasting with the positivity in as many as 15 (41%) of 37 patients with chronic persistent hepatitis, in 45 (94%) of 48 patients with chronic active hepatitis, and in 40 (87%) of 46 patients with liver cirrhosis with or without hepatocellular carcinoma. The mean +/- SE titer of antibody in chronic persistent hepatitis (3.8 +/- 0.9) was significantly lower than those in chronic active hepatitis (13.8 +/- 3.2) and cirrhosis with or without carcinoma (25.6 +/- 6.1) (p less than 0.001). Based on the results obtained, the antibody may reflect hepatic injury in the persistent hepatitis B virus infection.     

Serodiagnosis of viral hepatitis A by a solid-phase radioimmunoassay specific for IgM antibodies

A solid-phase radioimmunoassay for detecting specific IgM antibodies to hepatitis A virus (HAV) was developed and characterized. The test utilized microtiter plates coated with anti-IgM to specifically absorb the IgM antibodies from the test serum. The anti-hepatitis A IgM antibodies are measured by the specific consecutive binding of hepatitis A antigen and radiolabelled anti-hepatitis A antibodies (anti-HA). In 6 chimpanzees infected with HAV, IgM anti-HA was detected from about the first date of elevated transaminases and was positive for about 3 months. The usefulness of the test was confirmed by testing acute phase sera of 30 patients from a common source outbreak of epidemic hepatitis, and negative sera from 2 control groups. A collection of serum specimens from 190 patients with sporadic HBsAg-negative hepatitis in Brazil was also tested and an etiologic association with HAV was confirmed in the majority of these cases.     

Visceral larva migrans: Immunoglobulins, precipitating antibodies and detection of IgG and IgM antibodies against Ascaris antigen.

Serum samples from ten children with visceral larva migrans were evaluated by analysis of: immunoglobulin concentrations, precipitin reactions against Toxocara and Ascaris antigens and blood group substances, and IgM and IgG activity against Ascaris antigen by radioimmunoassay (RIA). The elevated concentrations of serum IgE and IgG and the positive precipitin reactions which occurred in some cases are an aid in diagnosis but were not consistently present. Serum IgM concentrations were elevated in all cases. IgM or IgG antibodies against Ascaris suum antigen were detected in all cases by a solid phase RIA technique. Radioimmunoassay techniques of this type may provide a superior method of diagnosis, particularly if used with serial serum samples which demonstrate changing levels of antibodies.     

IgM antibody response in acute hepatitis C viral infection.

IgM antibody against hepatitis C virus (IgM anti-HCV) was measured in serial samples from 15 transfusion recipients in whom posttransfusion chronic non-A, non-B hepatitis (NANBH) developed and three plasmapheresis donors during acute HCV infection using recombinant proteins derived from three immunodominant regions: core, NS-3, and NS-4 (c100). IgM anti-HCV core was detected in 13 of 15 posttransfusion patients. Nine of these patients had transient, acute-phase IgM anti-HCV core detected coincidentally or earlier than active IgG anti-HCV core response. The average duration of IgM anti-HCV core reactivity was 8.1 +/- 3.7 weeks. One patient lacking an IgM anti-HCV core response had detectable IgM anti-HCV NS-3 during the acute phase. Passive transfer of IgM anti-HCV was not observed in these posttransfusion cases, in contrast to the high frequency observed for IgG anti-HCV. Late IgM anti-HCV was detectable against core, c100, and NS-3 in three, two, and one posttransfusion patients, respectively. These data indicate that IgM anti-HCV core is a useful acute-phase marker in HCV infection.     

Preparation and characterization of human monoclonal antibodies directed against the hepatitis B virus surface antigen

The hepatitis B surface antigen (HBsAg) is highly immunogenic and induces an antibody response which is protective in vivo against hepatitis B virus (HBV) infection. Human monoclonal antibodies specific for HBsAg were produced, which could have potential therapeutic applications. Lymphocytes obtained from a vaccinated donor were stimulated in vitro and fused with the human myeloma cell line GM 4672, and eight hybridomas were obtained. Three of these clones, which reacted in an ELISA against the HBsAg vaccine, were expanded, subcloned and further analyzed. The subclones E7C2, C4C10, and D5B2 were able to bind to different HBsAg preparations, which express various subtypes, and recognized the major HBsAg peptides in Western blot analysis. Cross-inhibition experiments showed that E7C2, C4C10 and D5B2 are directed against the same epitope and have an affinity constant ranging from 5 X 10(7) to 3.3 X 10(9) M. Furthermore, these antibodies stained the surface and cytoplasm of the HBsAg-secreting cell lines PLC/PRF/5 and 4.10. The production of immunoglobulins varies from 0.3 to 1.3 micrograms/ml/10(6) and has remained stable over a period of 8 months. These human monoclonal antibodies, which appear to be directed against an antigenic determinant common to all HBsAg subtypes, could be useful in the study of HBV-related liver diseases as well as in their diagnosis and experimental therapy.     

The role of Epstein-Barr virus in acute and chronic hepatitis

BACKGROUND/AIMS: Epstein-Barr virus has a seroprevalence of more than 80% world wide and is known to be associated with hepatitis. However, little is known about the underlying pathogenesis and immunmechanisms and no standard diagnostic criteria to diagnose EBV-hepatitis are available. METHODS: We collected liver biopsies (n=21) with the tentative diagnosis of EBV induced hepatitis according to pathological changes and traceable EBV genome by PCR. Correlation with serological data revealed acute in seven cases, convalescent in two cases, past EBV infection in six cases. Viral RNA was visualised by in situ hybridisation within nuclei of lymphocytes. RESULTS: In seven of 68 liver biopsies with the diagnosis 'liver disease of unknown aetiology' EBV genome in the tissue was demonstrated indicating a possible role for EBV in the induction of hepatitis or a trapping of infected lymphocytes within the liver. In a control group of 20 EBV-seropositive patients with steatohepatitis EBV-DNA PCR of the liver tissue was negative. Immunohistochemistry identified CD3 and CD8 positive T-lymphocytes as the main lymphocytic infiltrate in EBV hepatitis. CONCLUSIONS: EBV hepatitis should be taken into consideration in case of typical histopathological changes and a positive DNA PCR of liver biopsy. Serological confirmation of the diagnosis is inevitable.     

Detection of antibodies against hepatitis C virus in saliva: a marker of viral replication

Hepatitis C surveillance has been restricted owing to the lack of a sensitive antibody assay for saliva. The aim of our study was to develop and evaluate a screening assay for hepatitis C antibody in saliva specimens. Serum/saliva pairs were collected from 115 hepatitis C-positive patients. A modified hepatitis C antibody assay for saliva was developed and linked to testing carried out in the diagnostic laboratory. Correlation between the presence of antibody in serum and in saliva was poor (100% vs 85%). However, of 98 patients who were saliva antibody positive, 96 (98%) were also serum hepatitis C RNA positive and two (2%) were serum hepatitis C RNA negative. Hence, the correlation between a positive salivary antibody test and the serum hepatitis C RNA status of intravenous drug users suggests that this test could be used as a surrogate marker for hepatitis C viraemia in epidemiological studies.