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Query: UMLS:C0019158 (
hepatitis
)
30,205
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
To analyse the effect of strain-specific sequence variation on the antigenic properties of the protein encoded by the open reading frame 3 (ORF 3) of hepatitis E virus (HEV), two sets of short overlapping peptides spanning amino acids 91 to 123 of this protein from Burmese and Mexican strains were synthesized and tested with sera obtained from outbreaks of enterically transmitted non-A, non-B
hepatitis
in three different regions of the world (Mexico, Turkmenistan and Kenya). The data suggest strain-specific variation in the antigenic reactivity of the ORF 3 protein. The C-terminal region of this protein contains several antigenic epitopes located in the most variable positions. Individual sera were found to interact with different groups of epitopes from each set of peptides. The antigenic epitopes of the Mexican strain appear to be less conformation-dependent than those of the Burmese strain. The most immunoreactive epitope of the ORF 3 protein from the Mexican strain was localized at amino acid positions 95 to 101. The ORF 3 protein of the Burmese strain contains an immunodominant epitope at amino acid positions 112 to 117. Some of these short peptides may be useful for the development of a diagnostic assay to discriminate between the Burmese and Mexican strains.
J
Gen
Virol 1994 Mar
PMID:Comparative characterization of antigenic epitopes in the immunodominant region of the protein encoded by open reading frame 3 in Burmese and Mexican strains of hepatitis E virus. 812 61
From a blood serum of patients with chronic posttransfusional non-A, non-B
hepatitis
the genomic RNA of hepatitis C virus (HCV) was isolated. Using RT-PCR (reverse transcription-polymerase chain reaction) there were synthesized and cloned cDNA fragments, representing 3 regions of the genome of a new virus isolate (HCV-R): 5'-nontranslating region, a core gene and a part of the nonstructural region NS3/NS4. Analysis of the nucleotide and of the amino acid sequences of a core and NS3/NS4 regions revealed significant difference between isolates from Russia (HCV-R) and from Japan (HCV-J). Nucleotide sequence homology between them was 90.0-90.87%, while homology between Russian and American isolates (USA-PT) complised 95.27-97.32%. No essential variations were found in the nucleotide sequences of 5'-nontranslating region of all three HCV isolates.
Mol
Gen
Mikrobiol Virusol
PMID:[Determination of the nucleotide sequence of the Russian variant of the hepatitis C virus]. 813 50
Hepatitis delta antigen (HDAg), the only protein encoded by the
hepatitis
delta virus (HDV), binds specifically genomic and antigenomic strands of the HDV RNA. In a previous study, three recombinant HDAg subdomains were synthesized, covering residues 11 to 78, 79 to 163 and 164 to 212, and only the middle domain was shown to be responsible for the binding to HDV RNA. To investigate HDAg sequences involved in HDV RNA binding, we synthesized five peptides, 15 to 29 residues in length, and tested their ability to bind HDV RNA using a simple non-radioactive ELISA with digoxigenin-labelled HDV genomic or antigenomic RNA probes. The specificity of interactions was demonstrated by comparison with control peptides and non-HDV RNA probes, and with an inhibition assay using recombinant HDAg. The HDAg-binding domain found within the middle region (79 to 163) of HDAg was more finely mapped: it is located between residues 79 and 107. In addition, another domain (residues 2 to 27) of HDAg was also found to bind specifically to HDV RNA. These two peptides share sequence similarities at residues 2 to 10 and 97 to 107 with other RNA-binding domains.
J
Gen
Virol 1993 Nov
PMID:Characterization of RNA-binding domains of hepatitis delta antigen. 824 65
1. Injection of lipopolysaccharides (LPS) or endotoxin into mice and rats induces a prolonged increase in serotonin (5-hydroxytryptamine: 5HT), predominantly in the liver. 2. The 5HT increase reflects the accumulation of platelets in the sinusoidal and perisinusoidal Disse spaces (spaces between endothelial cells and hepatocytes) in the liver. 3. Most of the platelets which accumulated in these spaces still retained their intact structure and a large amount of 5HT. 4. Interleukin-1 and/or tumor necrosis factor also induce the platelet response. 5. Kupffer's cells play a key role in this platelet response. 6. Anti-platelet drugs currently used, except for anti-inflammatory steroids, were ineffective in preventing the platelet response. 7. This platelet response is different from the well known platelet aggregation. 8. The possible involvement of this platelet response in insulin-independent hypoglycaemia, disseminated intravascular coagulation, septic shock,
hepatitis
, Shwartzman type reactions or self-defense mechanisms is discussed.
Gen
Pharmacol 1993 Sep
PMID:Active translocation of platelets into sinusoidal and Disse spaces in the liver in response to lipopolysaccharides, interleukin-1 and tumor necrosis factor. 827 Jan 61
None of the mutations so far discovered in several
hepatitis
delta virus (HDV) isolates appears to determine important changes in HDV specific protein (HDAg) expression, except for a putative mutation at nucleotide 1012 converting an amber stop codon (TAG) to a codon for tryptophan (TGG). Here we present the characterization of an HDV obtained from the liver of a woodchuck inoculated with sera from fulminant HDV patients in Central African Republic (CAR). By restriction enzyme analysis and sequencing of HDAg-coding region cDNA clones, we found that this HDV isolate bears a novel mutation (T to A) at nucleotide 1013 which converts the amber stop codon (TAG) to a codon for lysine (AAG). Comparison of these nucleotide sequences with those available from American, Japanese, Taiwanese, French, Italian and Nauru isolates showed a variability of 1.7 to 21.5% and 1.9 to 28.7% at the nucleic acid and amino acid levels, respectively. The HDAg-encoding sequence of the CAR isolate is closely related to that of the Italian HDV isolate. The in vitro expression of this HDV isolate resulted in a unique HDAg species (28K) which was identical with that characterized in vivo.
J
Gen
Virol 1993 Sep
PMID:Discovery of a novel point mutation changing the HDAg expression of a hepatitis delta virus isolate from Central African Republic. 837 62
A cDNA copy of the murine coronavirus [otherwise known as murine
hepatitis
virus (MHV)] surface (S) glycoprotein gene was isolated and expressed in DBT cells by using a recombinant vaccinia virus system. The expressed S protein induced extensive syncytium formation at neutral pH. Oligonucleotide mutagenesis was used to engineer an S protein gene in which codons for the proteolytic cleavage site, Arg-Arg-Ala-Arg-Arg, were replaced with an equal number of codons for amino acids with aliphatic or aliphatic hydroxyl side-chains. The mutated S protein was stably expressed in DBT cells and, in contrast to the wild-type protein, was not proteolytically cleaved. Nevertheless, the non-cleaved protein induced extensive syncytium formation. These results clearly indicate that the non-cleaved form of the MHV S protein is able to mediate cell membrane fusion. Thus proteolytic cleavage is not an absolute requirement for fusion activity.
J
Gen
Virol 1993 Feb
PMID:Proteolytic cleavage of the murine coronavirus surface glycoprotein is not required for fusion activity. 838 59
The 454-amino acid nucleocapsid (N) protein of mouse
hepatitis
virus (MHV) binds the leader RNA sequence located at the 5' ends of all plus-sense genomic and subgenomic viral mRNAs. Purified N protein was cleaved with formic acid to determine which domain interacts with the leader RNA sequence. Incubation at 42 degrees C resulted in partial cleavage into two fragments of M(r)s of approximately 32K and 37K and three fragments of 17K, 16K and 14K. Incubation at 56 degrees C resulted in complete cleavage yielding only the three lower molecular mass products. Both the 32K and 37K partial cleavage products and one of the complete cleavage products bind MHV leader RNA, suggesting that the central region of the N protein contains the RNA-binding domain. Monoclonal antibody mapping of the cleavage products confirmed that the MHV leader RNA binding domain is contained within the central 140-amino acid fragment, comprising amino acids 169 to 308. Analysis of the amino acids within this domain indicates no similarity to any previously described RNA-binding protein, suggesting that N protein may possess a unique RNA-binding motif.
J
Gen
Virol 1993 Sep
PMID:Localization of the RNA-binding domain of mouse hepatitis virus nucleocapsid protein. 839 88
Infection with the mouse
hepatitis
coronavirus (MHV) provides an excellent model for the study of viral diseases of the central nervous system and the gastrointestinal tract. With the ultimate aim of studying mucosal immunity to MHV we have cloned the genes encoding the structural proteins of MHV strain A59 (MHV-A59) into the E3 region of a human adenovirus type 5 vector. Infection of HeLa cells with the resulting recombinant adenoviruses AdMHVS, AdMHVN and AdMHVM revealed the correct expression of the spike (S), nucleocapsid (N) and membrane (M) proteins, respectively. Intraperitoneal inoculation of BALB/c mice with the recombinant viruses elicited serum antibodies which specifically recognized the respective MHV proteins in an immunoprecipitation assay. Only antibodies to the S protein neutralized MHV-A59 in vitro but titres were low. When analysed by ELISA or by immunofluorescence only the antibody response to the N protein was significant; weak responses or no detectable response at all were found for S and M, respectively. Upon intracerebral challenge with a lethal dose of MHV-A59 we found that a significant fraction of animals vaccinated with adenovirus vectors expressing either the S protein or N protein were protected. This protective effect was significantly stronger when the animals were given a booster immunization with the same vector prior to challenge. No protection was induced by AdMHVM. Interestingly, enhanced protection resulted when AdMHVS and AdMHVN were applied in combination as compared to survival after single immunizations. The results indicate that both the N and S proteins generate a protective immune response and suggest that this response is enhanced by combined expression of the two proteins.
J
Gen
Virol 1993 Oct
PMID:Mouse hepatitis virus spike and nucleocapsid proteins expressed by adenovirus vectors protect mice against a lethal infection. 840 30
We have analysed abnormal virus RNAs produced from integrated woodchuck
hepatitis
virus (WHV) sequences in two woodchuck liver tumours. Analysis of cDNA clones revealed that these transcripts consisted of rearranged, virus-specific RNAs encoding the WHV surface antigens. In one tumour, transcription was driven by the major preS2/S promoter and terminated at a cryptic poly(A) signal in the 5' end of the P gene, giving rise to a truncated version of the normal viral S message. In contrast, the integrated preS2/S promoter remained silent in the second tumour. The start sites of two abundant WHV transcripts encoding the large and middle surface proteins were localized about 100 bp upstream and 300 bp downstream of the preS1 translation initiation codon, corresponding to minor start sites of the normal surface protein mRNAs in chronically infected liver. Thus, the preS1 promoter, a weak promoter in episomal replicative forms of the virus, was activated in the integrated state in this tumour. Our results indicate that alternative usage of the preS1 or the preS2/S promoter in the integrated state may yield differential production of the three virus surface proteins in woodchuck liver tumours.
J
Gen
Virol 1996 Feb
PMID:Unusual activation of the integrated preS1 promoter of woodchuck hepatitis virus in a liver tumour. 862 20
Hepatitis C virus (HCV) isolates from 126
hepatitis
patients in Jakarta, Indonesia were genotyped by PCR with genotype-specific primers deduced from the HCV core gene. Fifty-five isolates (44%) were classified as genotype II/1b, 15 (12%) as 1c, 33 (26%) as III/2a, and 1 (1%) as V/3a, while the remaining 22 (17%) were not classifiable into any of the five common genotypes (I/1a, II/1b, III/2a, IV/2b and V/3a) or 1c. Sequences of a part of the NS5b region [1093 bp (nucleotides 8279-9371)] of the 22 isolates of unclassifiable genotype were subjected to pair-wise comparison and phylogenetic analysis along with those of 62 isolates of 25 genotypes in nine genetic groups. Seven of the isolates were classified into 2e and two into 2f, representing novel genotypes in genetic group 2, while ten and three were classified into two new genetic groups, 10 and 11, respectively, and their genotypes were provisionally designated 10a and 11a. The isolates of genotype 10a (JK049) and 11a (JK046) were sequenced in full. Comparison of 24 HCV genomes including those of JK049 and JK046, over the entire genome and subgenomic regions, supported the classification of HCV into 11 genetic groups.
J
Gen
Virol 1996 Feb
PMID:Hepatitis C virus variants from Jakarta, Indonesia classifiable into novel genotypes in the second (2e and 2f), tenth (10a) and eleventh (11a) genetic groups. 862 33
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