Coexpression of soluble and membrane-bound avian influenza virus H5 by recombinant Newcastle disease virus leads to an increase in antigen levels.

Newcastle disease virus (NDV) vectors expressing avian influenza virus (AIV) haemagglutinin (HA) of subtype H5 simultaneously protect chickens from Newcastle disease (ND) as well as avian influenza (AI). The expressed, membrane-bound surface protein HA is incorporated into virions while soluble HA has been described as a potent antigen. We tested whether co-expression of both HA variants from the same NDV vector increased the overall level of HA, which could be important for optimal immunogenicity.

Avian paramyoxvirus-8 immunization reduces viral shedding after homologous APMV-8 challenge but fails to protect against Newcastle disease.

Background: Protection against infection by Newcastle disease virus (NDV), also designated as avian paramyxovirus subtype-1 (APMV-1), is mediated by immune responses to the two surface glycoproteins, hemagglutinin-neuraminidase (HN) and fusion (F) protein. Thus, a chimeric APMV-1 based vaccine that encodes APMV-8 HN- and F-proteins and expresses the hemagglutinin of avian influenza virus (AIV) H5N1, is able to protect against HPAIV H5N1 but fails to protect against NDV [PLoS One8:e72530, 2013]. However, it is unclear whether avirulent APMV-subtypes, like APMV-8 can induce subtype-specific immunity and protect from a homologous challenge.

Chimeric newcastle disease virus protects chickens against avian influenza in the presence of maternally derived NDV immunity.

Newcastle disease virus (NDV), an avian paramyxovirus type 1, is a promising vector for expression of heterologous proteins from a variety of unrelated viruses including highly pathogenic avian influenza virus (HPAIV). However, pre-existing NDV antibodies may impair vector virus replication, resulting in an inefficient immune response against the foreign antigen. A chimeric NDV-based vector with functional surface glycoproteins unrelated to NDV could overcome this problem.