Prediction of antigenic epitopes on HA, NA amino acid sequences of novel influenza A (H7N9) virus and analysis association between susceptibility and HLA-Ⅱalleles / 中国免疫学杂志

ABSTRACT

Objective:To compare the amino acid sequences difference of HA,NA novel influenza virus A/H7N9 isolates, decipher possible B cell epitopes and T cell epitopes of HA,NA protein,and analyze the association between susceptibility and HLA polymorphisms.Methods:The amino acid sequences of novel influenza A ( H7N9) virus were downloaded from Genbank.Phylogenetic trees were constructed based on the amino acid sequences of HA and NA by using software Clustal X and MEGA 4.0.B cell and T cell epitopes were respectively predicted with Protean software and NetMHCⅡ2.2 Server online server.Results:The homology of HA and NA proteins of H7N9 virus was high.10 B cell epitopes and 15 T cell epitopes were randomly distributed throughout HA sequence and 12 B cell epitopes and 9 T cell epitopes were randomly distributed throughout NA sequence.HLA-DRB1*0701 allele which was commonly observed in Northern Chinese population have a high binding affinity for 9-mer peptides of HA and NA proteins.Conclusion:The prediction of B and T cell epitopes of HA and NA proteins with multiple methods benefits the research and development of vaccine against human infection with avian influenza A H7N9 virus.HLA-DRB1*0701 allele may contribute to susceptibility to novel influenza A (H7N9) virus.H7N9 influenza virus is more easily spread in Urumqi,Harbin,Shandong Province,Liaoning Province,Beijing, Shijiazhuang and Tianjin of China.