VECTORMUNE^® ND (HERPES VIRUS TURKEY-NEWCASTLE DISEASE VECTOR)
A. CONSTRUCTION OF VECTORMUNE^® ND VACCINE
Newcastle disease virus consist of a single molecule stranded RNA. The ND virus genome
codes for 6 different proteins:
• Fusion protein (F) = fusion of viral envelope to cell membrane & fusion of infected cells to adjacent cells,
• Hemagglutinin neuraminidase (HN) = attachment to target cells and neuraminidase activity,
• Nucleo capsid (NP) = template for transcription and replication,
• Matrix (M) = virion assembly process,
• Large (L) = RNA polymerase,
• Phosphoprotein (P) = nucleocapsid polymerase.
The fusion protein mediates fusion of the viral envelope with the host cell plasma membrane, thereby enabling the penetration of the viral genome into the cytoplasm. After process of the F protein in the infected cells, the F protein reaches the plasma membrane. Then it mediates the fusion of infected cells with adjacent cells leading to plaque cell destruction (2).
Differences in virulence of specific Newcastle strains are determined primarily by structural variations of the viral fusion glycoprotein F (1). Depending of the cleavability of the precursor F0 protein by protease from the chicken, the virus is able to infect different cells of the organism, thereby inducing low or high pathogenicity of the virus.
Therefore immunity against F protein is a key factor of Newcastle protection for the chicken.

Ceva, the world leader in vector vaccine development, has created a new vaccine for Newcastle disease offering improved protection and better meeting the needs of the poultry industry: 

VECTORMUNE^® ND is a genetically engineered live HVT vaccine carrying the F gene of Newcastle Disease virus and is indicated for use in chickens.
The vaccine is based on live serotype 3 Marek virus vaccine : HVT
• There is no interference from MDA,
• The vaccine is applied at the hatchery,
• It induces long lasting immunity on birds due to the persistency of the HVT strain in the chickens. The vaccine expresses the Newcastle F protein that is the major immunogenic protein for Newcastle disease protection.

REFERENCES
1. OIE terrestrial manual 2009, chapter 2.3.14. Newcastle disease.
2. Merz DC, Scheid A and Choppin PW, Importance of antibodies to the fusion glycoprotein of paramyxoviruses in the prevention of spread of infection. J. Exp. Med. Feb 1980, 151, 275-288