Tumor necrosis factor-alpha and interleukin-4 in the blood sera of chronic hepatitis patients

The concentration of tumor necrosis factor-alpha (TNF-alpha) and interleukin-4 (IL-4) in the blood sera of chronic hepatitis patients was, on the average, reliably higher than in the control group. A more pronounced increase in the concentration of TNF-alpha in the blood sera was observed in patients with chronic hepatitis of viral etiology in comparison with toxic hepatitis. The pronounced cytokine response of type Th2, manifested by the excessive production of IL-4, was typical for hepatitis B virus and hepatitis C virus infections, but not characteristic of hepatitis D virus infection. The replication activity of hepatotropic viruses induced a powerful cytokine response. In the presence of active virus replication in patients with chronic hepatitis B the levels of both TNF-alpha and IL-4 in their blood sera proved to be reliably higher than in patients with hepatitis B virus in the interactive phase.     

Effect of concurrent acute infection with hepatitis C virus on acute hepatitis B virus infection.

OBJECTIVE--To investigate the possible interference with acute hepatitis B virus infection by co-infection with hepatitis C virus. DESIGN--Analysis of stored sera collected for transfusion transmitted viruses study in 1970s. SETTING--Four major medical centres in the United States. PATIENTS--12 recipients of blood infected with hepatitis B virus. MAIN OUTCOME MEASURES--In 1970s, presence of antibodies in hepatitis B virus and raised serum alanine aminotransferase concentration; detection of antibodies to hepatitis C virus with new enzyme linked immunoassays. RESULTS--Five of the 12 patients were coinfected with hepatitis C virus. Hepatitis B surface antigen was first detected at day 59 in patients infected with hepatitis B virus alone and at day 97 in those coinfected with hepatitis C virus (p = 0.01); median durations of antigenaemia were 83 and 21 days respectively (p = 0.05), and the antigen concentration was lower in the coinfected patients. Alanine aminotransferase patterns were uniphasic when hepatitis B virus infection occurred alone (range 479-2465 IU/l) and biphasic in patients with combined acute infection (no value > 380 IU/l; p = 0.0025). Four coinfected recipients developed chronic hepatitis C virus infection. The fifth patient was followed for only four months. CONCLUSIONS--Acute coinfection with hepatitis C virus and hepatitis B virus inhibits hepatitis B virus infection in humans, and onset of hepatitis B may reduce the severity of hepatitis C virus infection but not frequency of chronicity. Alanine aminotransferase concentration showed a biphasic pattern in dual infection.     

The characteristics of an outbreak of non-A, non-B hepatitis with a fecal-oral mechanism of the transmission of the causative agent in Osh Province, the Kirghiz SSR

The results of epidemiological, clinical and laboratory studies revealed that the sharp rise of morbidity in viral hepatitides in Osh Province, the Kirghiz SSR in autumn 1987 was caused by hepatitis non A, non B virus with fecal-oral transmission. At this period the results of the enzyme immunoassay showed the absence of the markers of hepatitides A, B and Delta in 72.2% of viral hepatitis patients. Hepatitis non A, non B occurred only in 2.4% of viral hepatitis patients of preschool age (of these, 83.3% had hepatitis A) and was diagnosed in autumn 1987 in 50% of the patients aged 7-14 years and in 97.4% of the patients aged 15-29 years (in the latter age group 95-98% of the patients had IgG to hepatitis A virus in their blood). The appearance of the outbreak of the above-mentioned infection in Kirghizia is linked with the water route of the transmission of the infective agent. The epidemiological and clinical signs, characteristic of fecal-oral hepatitis non A, non B in Kirghizia, were not different from those registered earlier in other republics of the Central Asia and could be used for the identification of this infection.     

Antibody to hepatitis B core antigen in chronic active hepatitis.

Antibody to hepatitis B core antigen (anti-HBc), which has been assumed to be a more sensitive indicator of hepatitis B virus replication than hepatitis B surface antigen (HBsAg), was detected in the sera of 26 of our 65 patients with HBsAg-negative chronic active hepatitis. Thus despite the absence of HBsAg the liver disease could be the consequence of chronic infection with hepatitis B virus in these patients. They differed, however, from a group of 35 patients with HBsAg-positive hepatitis in being older on average and having less active liver lesions. The two groups could represent either two stages of chronic infection with hepatitis B virus or two types of response to it.     

Spread of hepatitis B viruses in vitro requires extracellular progeny and may be codetermined by polarized egress

Viruses can spread by different mechanisms: via intracellular particles through cell junctions to neighboring cells or via secreted virions to adjacent or remote cells. The observation of clusters of hepadnavirus-infected cells both in vivo and in primary hepatocytes neither proves the first mechanism nor excludes the second. In order to test which mechanism, if not both, is used by hepatitis B viruses in order to spread, we used primary duck hepatocytes and duck hepatitis B virus (DHBV) as an infection model. If extracellular progeny virus alone determines spreading, neutralizing antisera or drugs blocking virus binding to hepatocytes should abolish secondary infection. In order to test this, we used DHBV envelope-specific neutralizing antisera, as well as suramin, a known inhibitor of infection. Both reagents strongly reduced hepatocellular attachment of viral particles and almost completely abolished primary infection, whereas an ongoing intracellular infection was not affected as long as no progeny virus was released. In contrast, incubation of infected primary hepatocytes with these reagents during release of progeny virus completely prevented secondary infection. Moreover, the combination of electron and immunofluorescence microscopy analyses revealed the residence of viral particles in cytoplasmic vesicles preferentially located near the basolateral membrane of infected hepatocytes. Taken together, these data strongly suggest that hepatitis B viruses mainly spread by secreted, extracellular progeny and point to polarized egress of viral particles into intercellular compartments, which restricts their diffusion and favors transmission of virus to adjacent cells.     

Personalized therapy in chronic viral hepatitis

Chronic carriers of major hepatitis viruses (i.e., hepatitis B and C viruses, HBV and HCV) account for at least 600 millions people worldwide. About 50% of them are at risk for chronic hepatitis and 20-30% of patients with chronic hepatitis develop progressive liver disease and symptomatic life-threatening liver lesions. Therefore, the identification of the carrier at risk is mandatory to prevent progressive liver disease, avoiding non-appropriate treatments. The decision making has three major steps. The 1st is the identification of the patient who needs to be treated; the 2nd is the choice of the best therapeutic strategy and the most appropriate drugs and timing during the phase of infection and disease; the 3rd is the treatment optimization to reduce non effective therapy and avoid drug resistance virus mutants. This careful evaluation takes into account the individual variability, the host/virus interplays and the drug impact on viral replication with the risk of selection of resistant mutants. The complexity of the virus/host interactions, however, cannot be managed by simple mean of probabilistic statistics and/or step-wise algorithms based on population statistics. A better answer for personalized antiviral therapy may come from the combined use of molecular biology and bio-mathematical modeling that can help the medical doctor to follow the dynamic of viral infection during therapy, like the flight simulator helps the pilot. We provide a concise review of the potentials of this approach in clinical practice.     

Itinerary of hepatitis B viruses: delineation of restriction points critical for infectious entry

Little is known about cellular determinants essential for human hepatitis B virus infection. Using the duck hepatitis B virus as a model, we first established a sensitive binding assay for both virions and subviral particles and subsequently elucidated the characteristics of the early viral entry steps. The infection itinerary was found to initiate with the attachment of viral particles to a low number of binding sites on hepatocytes (about 10(4) per cell). Virus internalization was fully accomplished in less than 3 h but was then followed by a period of unprecedented length, about 14 h, until completion of nuclear import of the viral genome. Steps subsequent to virus entry depended on both intact microtubules and their dynamic turnover but not on actin cytoskeleton. Notably, cytoplasmic trafficking of viral particles and emergence of nuclear covalently closed circular DNA requires microtubules during entry only at and for specific time periods. Taken together, these data disclose for the first time a series of steps and their kinetics that are essential for the entry of hepatitis B viruses into hepatocytes and are different from those of any other virus reported so far.     

Major polypeptide of duck hepatitis B surface antigen particles

The 40- to 50-nm pleomorphic particles found in the sera of domestic Pekin ducks infected with duck hepatitis B virus were purified by rate zonal and isopycnic centrifugation. Sodium dodecyl sulfate-polyacrylamide gel electrophoretic polypeptide analysis of these particles, called duck hepatitis B surface antigen particles, revealed the major component to be a single 17,500-dalton polypeptide. This result is in contrast to polypeptide analyses of the surface antigens of related mammalian viruses, including hepatitis B, in which a major doublet of polypeptides is seen with molecular weights ranging from 23,000 to 29,000. Tryptic maps of 17,500-dalton polypeptide resembled that of the major non-glycosylated polypeptide of the adw subtype of hepatitis B surface antigen. A serological assay for antibody to the purified duck virus particles is also described.     

Serological relationship of woodchuck hepatitis virus to human hepatitis B virus.

Two antigenic systems of the woodchuck hepatitis virus have been identified. The relationship between viral antigens of the woodchuck hepatitis virus and the human hepatitis B virus was determined by using immunoprecipitation, hemagglutination, and immune electron microscopy techniques. Antigens found on the cores of the two viruses were cross-reactive. Lack of cross-reactivity between the surface antigens of the two viruses in immunodiffusion experiments suggested that the major antigenic determinants of the viral surfaces are different; however, results of passive hemagglutination tests indicated that there are common minor determinants. Nucleic acid homology, as measured by liquid hybridization, was found to be 3 to 5% of the viral genomes. The results of this study provide further evidence that woodchuck hepatitis virus is the second member of a new class of viruses represented by human hepatitis B virus. Since virus-infected woodchucks may acquire chronic hepatitis and hepatocellular carcinoma, these antigens and their respective antibodies will be useful markers for following the course of virus infection in investigations of the oncogenic potential of this class of viruses. The nucleocapsid antigen described may be a class-specific antigen of these viruses and, thus, may be useful in discovering new members of the group.     

Virus of Pekin ducks with structural and biological relatedness to human hepatitis B virus.

A virus found in the sera of Pekin ducks appears to be a new member of the human hepatitis B-like family of viruses. This virus had a diameter of 40 nm and an appearance in the electron microscope similar to that of human hepatitis B virus. The DNA genome of the virus was circular and partially single stranded, and an endogenous DNA polymerase associated with the virus was capable of converting the genome to a double-stranded circle with a size of ca. 3,000 base pairs. An analysis for viral DNA in the organs of infected birds indicated preferential localization in the liver, implicating this organ as the site of virus replication. In all of these aspects, the virus bears a striking resemblance to human hepatitis B virus and appears to be a new member of this family, which also includes ground squirrel hepatitis virus and woodchuck hepatitis virus.     

Seroprevalence of viral hepatitis in riverine communities from the Western Region of the Brazilian Amazon Basin.

The western region of the Brazilian Amazon Basin has long been shown to be a highly endemic area for hepatitis B and hepatitis D viruses. Data concerning the prevalence of hepatitis C and E viruses in this region are still scarce. In this study we investigated the presence of hepatitis A, B, C, D and E viruses infection in communities that live along the Purus and Acre rivers in the states of Acre and Amazonas within the Amazon Basin. A total of 349 blood samples were collected and tested for hepatitis A-E serological markers (antibodies and/or antigens) using commercial enzyme linked immunosorbent assays. Anti-HCV positive sera were further assayed by an immunoblot. HBsAg positive sera were subtyped by immunodifusion. The overall prevalence for hepatitis A, B, C, and E were 93.7%, 66.1%, 1.7%, and 4%, respectively. A very high prevalence of delta hepatitis (66.6%) was found among HBsAg positive subjects. Hepatitis A, B and D viruses were shown to be largely disseminated in this population, while hepatitis C and E viruses infection presented low prevalence rates in this region. The analysis of risk factors for HBV infection demonstrated that transmission was closely associated with sexual activity.     

A cDNA clone closely associated with non-A, non-B hepatitis.

A lambda gt11 cDNA library was constructed from RNA purified from hepatitis B viral surface antigen-negative human plasma with high alanine aminotransferase activity. A cDNA clone, designated as C8-2, was isolated by immunoscreening with mixed sera from non-A, non-B hepatitis (NANBH) carrier and convalescent chimpanzees. The recombinant protein produced by C8-2 reacted specifically with sera of patients in the chronic phase of NANBH. The sequence of C8-2, 269 bp, did not hybridized with any human or chimpanzee genomic DNA, and had no homology with those of primates and viruses. The existence of this sequence in RNA of possibly infectious plasma was shown by RNA blot hybridization and by Southern blot analysis of products amplified by the polymerase chain reaction. These results strongly suggest that C8-2 is derived from the agent of this viral hepatitis.     

Natural history and treatment of hepatitis B virus and hepatitis C virus coinfection

Hepatitis B virus (HBV) and hepatitis C virus (HCV) coinfection is not uncommon as a result of similar routes of infection. Patients who are coinfected represent a unique group with diverse serologic profiles. Combined chronic hepatitis B and C leads to more severe liver disease and an increased risk of hepatocellular carcinoma. Furthermore, coinfected patients represent a treatment challenge. No standard recommendations exist for treatment of viral hepatitis due to dual HBV/HCV infection, and therefore treatment must be individualized based on patient variables such as serologic and virologic profiles, patient's prior exposure to antiviral treatment, and the presence of other parenterally transmitted viruses such as hepatitis D virus and human immunodeficiency virus. The natural history and treatment of patients with HBV and HCV coinfection is reviewed.     

Isolation and characterization of a hepatitis B virus endemic in herons.

A new hepadnavirus (designated heron hepatitis B virus [HHBV]) has been isolated; this virus is endemic in grey herons (Ardea cinerea) in Germany and closely related to duck hepatitis B virus (DHBV) by morphology of viral particles and size of the genome and of the major viral envelope and core proteins. Despite its striking similarities to DHBV, HHBV cannot be transmitted to ducks by infection or by transfection with cloned viral DNA. After the viral genome was cloned and sequenced, a comparative sequence analysis revealed an identical genome organization of HHBV and DHBV (pre-C/C-, pre-S/S-, and pol-ORFs). An open reading frame, designated X in mammalian hepadnaviruses, is not present in DHBV. DHBV and HHBV differ by 21.6% base exchanges, and thus they are less closely related than the two known rodent hepatitis B viruses (16.4%). The nucleocapsid protein and the 17-kilodalton envelope protein sequences of DHBV and HHBV are well conserved. In contrast, the pre-S part of the 34-kilodalton envelope protein which is believed to mediate virus attachment to the cell is highly divergent (less than 50% homology). The availability of two closely related avian hepadnaviruses will now allow us to test recombinant viruses in vivo and in vitro for host specificity-determining sequences.     

Physical, chemical and morphologic dimensions of human hepatitis A virus strain CR326 (38578).

CR326 human hepatitis A virus purified by isopycnic banding from infected marmoset sera was shown to consist of 27 nm spherical particles on electron microscopic examination. The particles were identified as hepatitis A virus by tests for infectivity and by specific neutralization of infectivity with convalescent human hepatitis A serum. Also, indentical 27 nm viruses in liver extracts gave specific reactions with hepatitis A antisera when tested by immune electron microscopy. The bouyant density of the virus in CsCl was 1.34 and it was heat (60 degrees), ether and acid stable but was destroyed by heat (100 degrees), formalin (1:4000) and ultraviolet irradiation. Electron microscopic studies of sections of infected marmoset liver showed intracytoplasmic virus particles, usually in vesicles. Presumptive findings for RNA, together with the intracytoplasmic location of the virus, indicated the virus to be of RNA-type. The attributes of the virus indicate it is closely related to the enterovirus family and not to hepatitis B virus.     

IgM antibody against hepatitis B core antigen (IgM anti-HBc): diagnostic and prognostic significance in acute HBsAg positive hepatitis.

IgM antibody against hepatitis B core antigen (IgM anti-HBc), a marker of recent hepatitis B virus infection, was sought by radioimmunoassay in sera diluted 1/4000 from 376 patients presenting to four centres in Italy with acute, apparently type B hepatitis (hepatitis B surface antigen (HBsAg) positive). In 320 patients (85%) a positive IgM anti-HBc test result confirmed that hepatitis was due to primary infection with hepatitis B virus. In the remaining 56 patients absence of the IgM marker indicated that they were previously unrecognised long term carriers of HBsAg. Further serum analysis often showed delta infection and occasionally hepatitis A or cytomegalovirus infection as the true cause of their illness. After six to eight months circulating HBsAg persisted in 38 of 45 patients (84%) without IgM anti-HBc but in only six of 150 patients (4%) with the IgM antibody (p less than 0.0001). A negative IgM anti-HBc test result in patients with acute HBsAg positive hepatitis points to a factor other than hepatitis B virus as the cause of the liver damage and predicts the carriage of HBsAg.     

The epidemiological aspects of viral hepatitides in Estonia]

The etiological structure of viral hepatitides among the adult population of Tallinn and the occurrence of markers of hepatitis B and hepatitis C virus infections in medical workers, addict introducing drugs intravenously and hemodialysis patients were studied. Changes in the etiological structure of viral hepatitides were established: they took the form of a decrease in the level of hepatitis A morbidity and the considerable growth of the role of hepatitides B and C, as well as the newly detected circulation hepatitis D virus. About one-third in the structure of morbidity in viral hepatitides were hepatitis cases without markers of hepatitis A, B or C viruses (non-A, non-B, non-C). The highest rates of hepatitis B virus infection (78.9%) and hepatitis C virus infection (82.5%) were detected among drug addicts. Their level of HBsAg was 8.8%. In the group of medical workers, 25% of the examinees, i.e. every fourth person, had markers of hepatitis B virus, while antibodies to hepatitis C virus were detected in 5% of cases. Among hemodialysis patients these rates were 21.4% and 10.7% respectively.     

A structural protein of hepatitis C virus expressed in E. coli facilitates accurate detection of hepatitis C virus.

A putative core protein derived from hepatitis C virus was expressed in E. coli. More than 5% of the total protein expressed in the bacteria after induction by isopropylthio-beta-D-galactoside was shown to be the expected protein. Western blotting with this E. coli lysate proved to be more efficient than ELISA with a non-structural viral protein, C100, to detect infection of hepatitis C virus in the sera of patients with non-A, non-B chronic hepatitis, hepatocellular carcinoma as well as in sera from healthy persons.