Antigen capture ELISA for specific detection of influenza A virus NS1 protein

Objective: To develop a capture enzyme-linked immunosorbent assay (ELISA) for influenza A virus nonstructural protein NS1 using two anti-NS1 monoclonal antibodies (McAb) that map to distinct sites on the protein and to detect the NS1 in the culture supernatant and cell lysis supernatant of influenza virus. Methods: Among the McAb against influenza A virus NS1, antibody pairs were analyzed to choose the optimal coating McAb and detecting McAb by determinating the detection sensitivity and specificity. Results: The capture ELISA efficiently detected as little as 240 pg/ml of recombinant NS1 protein and exhibited no cross-reactivity for influenza B virus, parainfluenza virus NS1. Conclusion: A sensitive and specific NS1-based capture ELISA for influenza A virus NS1 was successfully established, which could be an important tool for diagnosis of influenza A virus infection.