Expression of a secreted version of the hemagglutinin-neuraminidase glycoprotein of Newcastle disease virus: its evaluation as a diagnostic reagent

CHIMENO ZOTH S.A; GOMEZ, E; CARBALLEDA J. M.; CARRILLO, E; BERINSTEIN, A

JOURNAL OF VETERINARY DIAGNOSTIC INVESTIGATION

AMER ASSOC VETERINARY LABORATORY DIAGNOSTICIANS INC

Año: 2010 p. 519 - 523

1040-6387

The hemaglutinin-neuraminidase (HN) glycoprotein of Newcastle disease virus (NDV) constitutes, together with the fusion glycoprotein, the main surface antigen of this avian pathogen which causes a highly contagious disease, relevant economically worldwid. The purpose of this work was to obtain the HN glycoprotein as a soluble antigen in culture supernatants of recombinant baculovirus-infected Sf9 cells and to evaluate its application to the development of a recombinant enzyme-linked immunosorbent assay (ELISA) for the analysis of chicken sera. A transfer vector for baculovirus containing the sequence of a mellitin signal peptide was constructed and the sequence coding for HN protein without its own signal peptide was cloned. The recombinant protein was secreted and recovered easily from the culture medium of Sf9 infected cells. The recombinant protein was evaluated as antigen for ELISA coating the plates with the recovered HN using 79 positive and 142 negative samples. The Cohen Kappa value resulted 0.91, indicating excellent agreement between the rELISA and the HI test. The rELISA was also compared with a commercial ELISA, finding high levels of agreement between both assays. The present results show that the cloning strategy developed yielded the HN protein free in the cell culture supernatant and that the recombinant protein retained its reactivity with anti-NDV HN antibodies in chicken sera.