Persistent and transient antibody responses to hepatitis E virus detected by western immunoblot using open reading frame 2 and 3 and glutathione S-transferase fusion proteins.

Abstract

Recombinant proteins containing amino acid sequences from open reading frame (ORF) 2 and ORF3 of a Chinese strain of hepatitis E virus (HEV) were constructed as fusions with glutathione S-transferase (GST). Stable fusion proteins were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the proteins were transferred to nitrocellulose membranes, and the immobilized proteins were probed with sera from hepatitis E patients from various regions or from rhesus monkeys (Macaca mulatta) experimentally infected with the Chinese strain of HEV. Immunoglobulin G-class antibodies were detected with chemiluminescence and anti-human immunoglobulin G conjugated to horseradish peroxidase. Anti-ORF3 antibodies were detected in most patients and monkeys within 17 days of exposure, but this humoral response declined with time and was usually undetectable by approximately 100 days. Anti-ORF2.1 antibody was usually detected as early as anti-ORF3 but persisted in all animals and many patients, whereas reactivity to the larger GST-ORF2.2 fusion protein was more transient, even though all sequences present in GST-ORF2.1 are present in GST-ORF2.2. Rechallenge of these monkeys with HEV suggested that immunity to reinfection was incomplete, as levels of anti-ORF2.1 (but not anti-ORF2.2) were boosted after each rechallenge. The results demonstrate that the carboxy-terminal region of HEV ORF2 contains epitopes which are recognized by convalescent-phase antibody and are likely to be associated with limited immunity to infection, but these epitopes may be masked when larger portions of ORF2 are expressed as recombinant proteins.

• Authors: F Li, H Zhuang, S Kolivas, S A Locarnini, D A Anderson
• Journal: Journal of clinical microbiology (J Clin Microbiol) Vol. 32 Issue 9 Pg. 2060-6 (Sep 1994) ISSN: 0095-1137 [Print] United States
• PMID: 7529246 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antigens, Viral
• Epitopes
• Hepatitis Antibodies
• RNA, Viral
• Recombinant Fusion Proteins
• Viral Proteins
• Glutathione Transferase

Topics

• Animals
• Antigens, Viral (genetics, immunology)
• Base Sequence
• Blotting, Western
• Epitopes (immunology)
• Glutathione Transferase (genetics)
• Hepatitis Antibodies (biosynthesis, blood, immunology)
• Hepatitis E (blood, immunology)
• Hepatitis E virus (genetics, immunology)
• Humans
• Macaca mulatta
• Molecular Sequence Data
• Open Reading Frames
• RNA, Viral (genetics)
• Recombinant Fusion Proteins (immunology)
• Viral Proteins (genetics, immunology)