Long term evolution of the region NS3 containing a CTL epitope of hepatitis C virus in three HCV infected men
Longterm evolution of the region NS3 containing a CTL epitope of hepatitis C virus in three HCV infected men$$$$ GUO Huazhang, WANG Wenliang, WANG Tao, et al. Department of Pathology, Fourth Military Medical University, Xi'an 710032 【 Abstract 】 Objective To study the sequence evolution of HCV NS3 in two HCV carriers and one recovered person over 6 years. Methods Three patients were exposed to HCV prior to 1991. Blood samples taken in 1991, 1994 and 1996 were analyzed for nucleotide sequences. HLA types of these three persons were determined using antibodies. CTL epitopes were predicted using MHC binding motif. Results A reported HLA A2 restricted CTL epitope showed no alteration in the HLA A2 negative carrier over six years. In the HLA A2 positive individuals, some of the sequences showed amber mutation on the initial codon of the epitope. Peptides with persistent amino acid transitions contained MHC binding peptide motif. Conclusion The amber mutations and persistent amino acid transitions may be related to the immune escape. 【 Subject words 】 Hepatitis C virus Tlymphocytes Viral protein