Identification of catalytically active domain epitopes in neuraminidase protein of H9N2 subtype of avian influenza virus

In this study, a truncated NA gene (205-900 bp) was cloned from the NA sequence of H9N2 strain, and then expressed using pET-28a (+) vector. This purified recombinant NA protein was used to immunize BALB/c mice, and the monoclonal antibodies were screened through the indirect enzyme-linked immunosorbent assay (ELISA). Next, eight prokaryotic expression vectors were constructed for epitope identification. After cell fusion, three hybridoma cell lines producing the antibodies special to NA protein were screened by ELISA, western blotting, and indirect immunofluorescence; these were named 1B10, 2B6, and 5B2, respectively. Epitope scanning techniques were used to identify three B-cell epitopes recognized by these three monoclonal antibodies, 196KNATASIIYDGMLVD210, 210DSIGSWSKNIL220 and 221RTQESECVCI230. The subsequent homology analysis revealed the three epitopes were highly conserved in H9N2 AIV strains. The structural predictions of the antigenic epitopes indicated that all three epitopes were located in the catalytic region of NA. These results provide a basis for studying the function of the NA protein of H9N2 AIV and technical support for the development of a universal detection method based on anti-NA monoclonal antibodies.PMID:37581283 | DOI:10.1080/03079457.2023.2239191

Source: Avian Pathology - August 15, 2023 Category: Pathology Authors: Xiangyu Huang Yiqin Cai Guihu Yin Zili Chen Jianing Hu Zichen Gao Xinyu Guo Fuqiang Xiong Xiuli Feng Source Type: research