Discrimination of influenza A subtype by antibodies recognizing host‐specific amino acids in the viral nucleoprotein

Abstract

Please cite this paper as: Miyoshi‐Akiyama et al. (2012) Discrimination of influenza A subtype by antibodies recognizing host‐specific amino acids in the viral nucleoprotein. Influenza and Other Respiratory Viruses 6(6), 434–441. Background Nucleoprotein (NP) of influenza viruses is utilized to differentiate between the A, B, and C viral serotypes. The availability of influenza genome sequence data has allowed us to identify specific amino acids at particular positions in viral proteins, including NP, known as “signature residues,” which can be used to discriminate human influenza A viruses from H5N1 highly pathogenic avian influenza in human cases (HPAI) and pandemic H1N1(2009) (H1N1/2009) viruses. Methods Screening and epitope mapping of monoclonal antibodies (mAb) against NP of influenza A, which reacted differently with NP from human influenza A virus from HPAI and H1N1/2009 A virus. To identify the epitope(s) responsible for the discrimination of viral NP by mAbs, we prepared mutant NP proteins in the 293 cell expression system because some of the mAbs reacted with non‐linear epitopes. Results and Conclusions In the present study, we identified 3 mAbs. The results of epitope mapping showed that the epitopes were located at the signature residues. These results indicated that signature residues of NP could discriminate influenza A viruses from different origin.

Surveillance Study of Influenza Occurrence and Immunity in a Wisconsin Cohort During the 2009 Pandemic

“…Nucleoprotein is highly conserved among viral strains. Some antibodies can distinguish pH1N1 NP from earlier strains [ 31 ], but polyclonal sera like ours mainly detect shared epitopes. Enzyme-linked immunosorbent assay was performed on rNP proteins of A/Brisbane/10/2007(H3N2), A/PR/8/34(H1N1), and pH1N1.…”

“…Protective mechanisms in animal models include antibodies to influenza NP and M2. Although NP is highly conserved, occasional antibodies recognize pH1N1 NP but not NP from seasonal viruses [ 31 , 38 ]. Our ELISA with polyclonal sera mainly detects the common antibodies to shared epitopes.…”

Nucleoprotein as a Promising Antigen for Broadly Protective Influenza Vaccines

“…Although NP-specific antibodies are considered highly cross-reactive, the use of anti-NP monoclonal antibodies revealed some variations in the antigenicity of this protein between evolutionarily diverse influenza viruses [ 127 ]. In addition, several mAbs have been described that can only bind to a specific subtype of influenza A virus, suggesting a critical influence of some NP residues on antibody binding [ 128 ]. In the study of Bodewes et al, human monoclonal anti-NP antibody bound diverse H1N1 and H3N2 viruses with different intensities, indicating variations in the affinity of the antibody for the respective NPs [ 19 ].…”

Detection of Avian Influenza Virus from Cloacal Swabs Using a Disposable Well Gate FET Sensor

“…Nucleoproteins (NP), on the other hand, are proteins internal to the virus and less subject to mutation. In this work, we present an AIV sensor that targets NPs, which are nearly identical across a wide range of subtypes and hence ideal for a multistrain point‐of‐care AIV detection device …”