Newcastle Disease Virus (NDV) Vecotred Vaccine Protects Chicken From Challenges Of Virulent NDV And Mycoplasma Gablsepitcam

Mycoplasma gallisepticum (MG) is the most economically significant mycoplasma pathogen of poultry, and has a world-wide distribution. Infection with MG has a wide variety of clinical manifestations, but even in the absence of overt clinical signs, the economic impact may be significant. In most countries, administration of suitable antibiotic medication is practiced to control MG outbreak. The use of antibiotics results drug residues in chickens and emerge of drug-resistant strains. Vaccination is a useful method protected chickens from MG infection when poultry flocks are exposured to wild type challenge. Both killed vaccines and live vaccines are currently used in worldwide. However, the poultry flocks are forbidden to use antibiotics for a long time before or after live vaccine inoculation. Killed MG vaccines prevent partly chickens from the severity of lesions and egg production losses upon challenge. At the same time, killed MG vaccine is expensive and the procedure of vaccination is tedious for chicken farmers. A safe, effective and cheap MG vaccine, especially live MG vaccine, is desired.Protein of Mycoplasma gallisepticum adhesin (pMGA) is membrane proteins. pMGA promote intimate contact between the mycoplasma and the target cell and plays a key function regarding interaction with the host cell and the ability to escape the immune system of host. vlhA.5.02gene family encode a series of lipoproteins including TM1which have been shown in capable of inducing protective humoral immunity in chickens.Newcastle disease virus (NDV) causes an economically lose in all species of birds worldwide. Over decades, NDV live vaccine LaSota strain has been used in commercial chickens throughout the word with records of efficacy and safety. LaSota strain grows to very high titers in chicken embryos and elicits strong humoral, cellular and mucous immune responses in vivo. LaSota strain is the promising and suitable live vaccine vector for the control and prevention of infectious diseases in poultry.In order to develop a safe and efficient recombinant MG vaccine based on of NDV LaSota vaccine strain as viral vector, we constructed and rescued a recombinant NDV which expressed TMl protein of MG (rLa-TMl) by reverse genetic techniques. The expression of MG TMl protein in recombinant virus was confirmed in the infected BHK cells by confocal immunofluorescence assay. Pathogenic test shown that the rLa-TMl retained its high-titer growth property and low pathogenicity in embryonated chicken eggs, MDT=132h, ICPI=0IVPI=0. Moreover, the rLa-TMl induced high titers of antibody responses against both NDV and MG and provided90%protection against MG and100%protection against NDV challenge. These results demonstrated that the rLa-TMl had the potential of being used as a bivalent NDV and MG vaccine.