摘要:

AbstractWe have cloned and sequenced an infectious, functionally active genome of a duck hepatitis B virus (DHBV). It is 3,021 base pairs (bp) in length and shows little DNA sequence homology to the genome of human hepatitis B virus (HBV). However, the amino acid sequences of predicted viral gene products are similar between DHBV and HBV, and the genome organization present in DHBV reflects that of HBV. As in the mammalian virus the long minus strand of the DHBV genome encodes three long overlapping reading frames designated as P, S, and C. The fourth open reading frame, termed X, is absent in DHBV. A comparison with a sequence of a second DHBV isolate [Mandart et al, Journal of Virology 49:782–792, 1984] revealed a nucleotide sequence variation of 5.6% and confirmed the presented overall gene organization of DHB

ISSN:0146-6615    

DOI:10.1002/jmv.1890150402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe nature of hepatitis B surface antigen (HBsAg)‐associated receptors for polymerized human serum albumin (pHSA‐R) and their relationship to hepatitis B e antigen (HBeAg) and human serum proteins have not been defined. We studied by radioimmunoassay and by electron microscopy HBsAg‐associated pHSA‐R secreted in vitro by a human hepatocellular carcinoma cell line (PLC/PRF/5) and by mouse 3T3 fibroblasts after transfection with cloned hepatitis B virus (HBV) DNA (4.10 cells). PLC/PRF/5 cells expressed only HBsAg, whereas 4.10 cells secreted also HBeAg. There was no significant difference in the production of HBsAg, HBeAg, and pHSA‐R when the cells were cultured in the presence or absence of fetal calf serum. Secretion of pHSA‐R by the two cell lines for a given amount of HBsAg was equal irrespective of the presence or absence of HBeAg. Supernatants from both cell lines grown in serum‐free medium did not contain any Clq or albumin when tested by immunodiffusion. The ability of a transfected mouse cell line to produce HBsAg with pHSA‐R activity strongly suggests that pHSA‐R is coded by the HBV genome and does not depend on the presence of human serum proteins. In addition, our findings fail to demonstrate any correlation between HBeAg prod

ISSN:0146-6615    

DOI:10.1002/jmv.1890150403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe risk of hepatitis B infections has been reduced by screening of blood donors for hepatitis B surface antigen (HBsAg). However, recipients remain at significant risk of developing post‐transfusion hepatitis. Studies have shown that non‐A, non‐B hepatitis virus(es) are responsible for the majority of post‐transfusion hepatitis infections. In spite of many efforts, these non‐A, non‐B hepatitis viruses have not yet been identified. Epidemiological studies, however, suggest that non‐A, non‐B hepatitis shares many features with hepatitis B. Recently, Wands et al [1982] showed, in chimpanzees infected with non‐A, non‐B hepatitis agents, the presence of antigenemia or viremia by radioimmunoassay with monoclonal antibodies directed toward distinct determinants of HBsAg and by molecular hybridization analysis. They suggested that non‐A, non‐B hepatitis agents may be related, but distinct variant(s) of hepatitis B virus (HBV). In this study, five chimpanzees were inoculated with three different agents that have been shown to transmit non‐A, non‐B hepatitis. The following inocula were used (I) a factor VIII preparation kindly provided by D.W. Bradley, (II) acute phase serum from a chimpanzee infected with the F strain kindly provided by A.J. Zuckerman, and (III) a DS‐antigen serum previously shown by us to transmit non‐A, non‐B hepatitis [Duermeyer et al, 1983]. All chimpanzees developed a rise in transaminase levels between 8 and 10 weeks after inoculation. None of the chimpanzees was positive for any markers of HBV infection. No evidence was obtained of infection with hepatitis A, cytomegalovirus, or Epstein‐Barr virus. One chimpanzee developed chronic liver disease. The presence of HBV DNA in sera and in liver biopsies was studied. HBV DNA hybridizable sequences were not detected in any of the samples collected at different stages of the disease. These findings suggest that the non‐A, non‐B hepatitis age

ISSN:0146-6615    

DOI:10.1002/jmv.1890150404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe hepatitis D virus (HDV; previously called the “delta agent”) is a defective organism which can replicate only in the presence of the hepatitis B virus (HBV). We tested the serum of 95 substance abusers, all of whom had sufficient evidence of chronic liver disease to warrant a liver biopsy, for hepatitis D virus antibody (anti‐HDV). Anti‐HDV was detected in five of eight hepatitis B surface antigen (HBsAg)‐positive patients and 12 of 87 (14%) HBsAg‐negative patients. Antibody to the hepatitis B core antigen (anti‐HBc) was the sole hepatitis B marker in eight of the 12 (67%) anti‐HDV‐positive, HBsAg‐negative patients but in only 14 of 75 (19%) anti‐HDV‐negative, HBsAg‐negative patients (P<0.005). None of the anti‐HDV‐positive, HBsAg‐negative patients had detectable IgM anti‐HBc in the serum or hepatitis D antigen in liver tissue, and they had similar clinical features and liver biopsy diagnoses to HBsAg‐negative patients without anti‐HDV. We conclude that anti‐HDV in HBsAg‐negative substance abusers reflects infection with HDV and HBV in the distant past and does not indicate more severe liver disease than that seen in

ISSN:0146-6615    

DOI:10.1002/jmv.1890150405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractAn extract prepared from the liver of a patient with chronic non‐A, non‐B (NANB) hepatitis was found to produce a precipitin line in immunodiffusion with a serum from a multiply transfused patient and those from patients convalescent from NANB hepatitis. The antigen was purified by gel filtration and density gradient centrifugation. The antigen had a buoyant density of 1.16–1.20 g/cm3in cesium chloride, a sedimentation coefficient (S20, w) of 51.5s, and a molecular weight of larger than 1.5 × 106daltons. Electron microscopic examination revealed particles 29–34 nm in diameter (average 31.5 nm), which could be agglutinated by the specific antiserum. We developed a reverse passive hemagglutination (R‐PHA) and a passive hemagglutination (PHA) technique for detection of the new antigen and antibody, respectively, and applied these to human sera. Antibody to the antigen was detected in 19/28 (67.9%) convalescent sera of NANB hepatitis. This prevalence was significantly higher than those found in convalescent sera of type A hepatitis patients (2/17 = 11.8%), type B hepatitis patients (2/15 = 13.3%), and normal blood donors (9/129 = 7.0%) (p<0.01); and the prevalence in hepatitis A and B patients did not differ significantly from that of normal donors. Furthermore, most (66.7%) of the cases of NANB hepatitis endemic in Shimizu City, Japan, showed clear seroconversion with respect to this antibody. These results suggest that the new antigen/antibody system is associated with NANB

ISSN:0146-6615    

DOI:10.1002/jmv.1890150406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractA biotin‐labeled DNA probe specific for hepatitis B virus (HBV) nucleotide sequences was hybridized in situ to liver tissue of 20 patients; 16 were chronic carriers of hepatitis B surface antigen (HBsAg) and 4 had no markers of HBV infection. HBV‐DNA was also analyzed in the serum and the liver of these patients by spot and Southern blot hybridization, respectively.Liver specimens from six carriers were positive for HBV‐DNA both by in situ and Southem blot hybridization; ten carriers were negative by in situ hybridiza‐ tion, and two of these were positive by Southern blot technique. The staining was granular, mainly cytoplasmic, limited to liver specimens containing replicative forms of HBV‐DNA, and associated with detection of HBcAg in hepatocytes by immunofluorescence. The sensitivity of this technique was not sufficient to detect few copies of integrated HBV‐DNA.The hybridization procedure was specific, as results were constantly negative in liver specimens of patients without markers of HBV infection, and no reaction was observed using DNA probes lacking HBV‐DNA sequences.Detection of HBV‐DNA by in situ hybridization, using a biotinylated probe, is a rapid, reproducible, and specific histochemical method. Currently available biotinylated probes are advantageous when absolute sensitivity is not the limiting factor, and they also facilitate studies of the cellular and subcellar distribution of HB

ISSN:0146-6615    

DOI:10.1002/jmv.1890150407

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractReceptors for polymerized human albumin are found at high litres during high‐level hepatitis B virus (HBV) replication and in small amounts in chronic low‐level infection. Complexes between hepatitis B surface antigen (HBsAg) and IgM without specificity for HbsAg are expressed in a pattern similar to that of receptors. Anti‐albumin antibodies could be involved in their formation. Delta infection depresses the synthesis of gene products of HBV. To assess whether delta modifies the expression of receptors on HBsAg and the level of HBsAg/IgM complexes, and if anti‐albumin antibodies are actually part of the complex, we tested sera from 86 subjects with acute and chronic HBV infection. Our findings show that the amounts of circulating receptors and HBsAg/IgM are proportional to the concentration of HBsAg and thus probably to the degree of viral replication. We did not find any correlation between circulating anti‐albumin antibodies of the IgM class and HBsAg/IgM complexes. Delta infection depresses HBsAg synthesis and causes a related decrease in receptors and HBsAg/IgM titres if superimposed on the more active stage of HBV infection. When HBsAg, receptors, and HBsAg/IgM are at low levels, no further depression is caused by delta infection. HBsAg/IgM titre is not enhanced by presence of anti‐delta antibodies, thus excluding a role of the latter in forming thes

ISSN:0146-6615    

DOI:10.1002/jmv.1890150408

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractSerial titres of rotavirus specific IgG and IgM have been measured in children and adults living in a small community over a 21/4‐year period. In all age groups the mean titres of rotavirus specific IgG and IgM rose and fell in parallel with the changes in frequency of gastroenteritis symptoms in the communily bul after the time when respiratory symptoms reached their peak.Gastroenteritis symptoms were seen most commonly in the children but were also frequent in adults, especially the women. Titres of rotavirus specific IgG changed with age, increasing through childhood into early adult life, but decreased thereafter only to increase again in those over the age of 50 years. Females had higher levels of IgG in all age groups but especially among the children and 30–49‐year‐old women. The high levels of IgG did not protect the young adults from symptomatic gastroenteritis.Detectable levels of rotavirus specific IgM occurred in all age groups but more commonly in children aged under 10 years and in young adults. Raised levels of IgM were uncommon in the elderly, who rarely suffered gastroenteritis symptoms.An epidemiological model is proposed in which the older members of the community act as a reservoir of rotavirus, passing the infection to the chidren, who then infect the young

ISSN:0146-6615    

DOI:10.1002/jmv.1890150409

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractThe bivalent form of an aqueous formalin‐inactivated hepatitis B vaccine was evaluated for safety and immunogenicity in chimpanzees. To evaluate safety five animals were inoculated intravenously with vaccine containing 500 μg HBsAg and two animals with 50 μg. None of these animals developed hepatitis or any serologic marker indicative of the presence of residual live vims in the vaccine.Twenty‐four animals were used to evaluate immunogenicity and protective efficacy. Seven of these immunized animals produced weak or no anti‐HBs responses. Two doses of 50 μg HBsAg given subcutaneously 1 month apart protected each of four animals that were challenged with 103.5CID50HBV at 6 and 12 months after immunization and protected three of four animals challenged at 24 months against development of hepatitis or HBsAg. Three of 4 animals in each group immunized with two doses of 20, 10, or 5 μg HBsAg were similarly protected when challenged 6 months after immunization.Thirteen of 20 immunized animals that did not develop HBsAg after challenge with HBV developed anamnestic anti‐HBs or anti‐HBc responses between 2 and 18 months after challenge, indicating minimal replication of challenge virus. The time of onset and frequency of occurrence of these delayed responses was related to the titer of anti‐HBs at the time of challenge.False positive Ausab test results were observed in quarantined chimpanzees. These were neither preceded by appearance of HBsAg nor accompanied by development of anti‐HBc. In most cases these reactions were due to a reactant having a sedimentation coefficient and an electrophoretic mobility resembling that of IgM. This reactant generally did not appear to confer resistance to challenge with HBV.The humoral immune response was characterized as being entirely of the IgM class 2 weeks after immunization and switched entirely into the IgG class by 10–12 weeks after vaccine administration. At the time of challenge all animals with antibody had an

ISSN:0146-6615    

DOI:10.1002/jmv.1890150410

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY

摘要:

AbstractTo provide background for future hepatitis A vaccine trials, sera were collected from 0‐ to 4‐year‐old Liberian infants and their mothers on two occasions an average of 14.75 months apart and tested for antibody to hepatitis A virus (anti‐HAV).Theprevalenceof anti‐HAV rose from 2.5% in infants 0–6 months of age to 70% in children 3–4 years of age and did not differ between male and female infants.The annualincidenceof new infections was slightly lower in the first year of life (35%) than in the subsequent 3 years, when it averaged 45%. The presence of HBV infection did not affect the incidence of HAV seroconversion. No clinical hepatitis was recognized in the subjects who seroconverted.Dual hepatitis A and B virus infection were observed; these were all clinically inapparent.The extraordinary incidence of HAV infection documented in the present study offers an opportunity for vaccine efficacy trials requiring minimal number

ISSN:0146-6615    

DOI:10.1002/jmv.1890150411

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1985

数据来源: WILEY