Nucleotide sequences of the hepatitis C virus core region in patients without anti-core antibody

✍ Scribed by Nagasaka, Atsushi; Hige, Shuhei; Kurosawa, Mitsutoshi; Yoshida, Junichi; Karino, Yoshiyasu; Toyota, Jyoji; Matsushima, Takashi; Asaka, Masahiro

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 444 KB
• Volume: 49
• Category: Article
• ISSN: 0146-6615
• DOI: 10.1002/(sici)1096-9071(199606)49:2<91::aid-jmv4>3.0.co;2-e

✦ Synopsis

Second-generation assays for detection of hepatitis C virus (HCV) infection that include reactivity of antibodies to core, NS3, NS4 are used because of their high sensitivity. Among these antibodies, anti-core antibody seems to be the most sensitive. However, there are some patients without anti-core antibodies, although HCV RNA is detectable by reverse transcription-polymerase chain reaction and branched DNA assay. The mechanism for the absence of anti-core antibody on its own is unclear. We therefore determined the nucleotide and deduced amino acid sequences of the core region obtained from two anti-core antibody-negative patients with HCV RNA (genotype I b ) and compared them with those of four anti-core antibody-positive patients and a previously reported sequence. Amino acids spanning 1-47, which seemed t o exist in major B cell epitopes, were found t o be completely conserved among these patients. Furthermore, the predictive binding motif to HLA DR4 (a.a 81-90) was completely conserved in both of the anticore antibody-negative patients. There were various mutations in the residual amino acids spanning 49-108, but specific mutations could not be found in anti-core antibody-negative patients.

These data indicate that the absence of anticore antibody in two patients is not due to the presence of some formerly unknown viral variants, but due to a possible defect in the host's immune system. o 1996 Wiiey-Liss, Inc.