Characterization of Bangor virus proteins by using monoclonal antibodies

A new virus was isolated from a finch in quarantine in Northern Ireland in 1973. The virus had the morphological characteristics of a paramyxovirus, and was named Bangor virus (BaV). In order to identify the structural proteins of BaV and to investigate the biological characterization of the virus, 28 monoclonal antibodies (mAbs) directed against BaV were prepared. Eight of these mAbs reacted with the nucleocapsid protein (NP), 10 with hemagglutinin-neuraminidase (HN) protein, and 10 with fusion (F) protein. With the aid of these mAbs, the structural proteins of BaV were determined, namely, p52, gp74, gp63, and gp51 were identified as the NP, HN, F0, and F1 proteins, respectively. The biological activities of the mAbs directed against the envelope glycoproteins of BaV were examined. Intriguingly, it was found in the neutralization assay that four mAbs directed against the HN protein of BaV can enhance the fusion of HeLa cells infected with BaV, showing the presence of a potential third function of the HN protein that affects the fusion activity of the F protein. Furthermore, all of the anti-F protein mAbs showed neutralizing activity.