Project Number: 6406-32000-008-00
Project Type: Appropriated

Start Date: Sep 01, 2004
End Date: Jan 31, 2007

Objective:
Optimize current Mycoplasma gallisepticum (MG) vaccination protocols for layer hens and determine the mechanisms by which MG vaccinations induce immunological changes. Design and produce an efficacious recombinant MG vaccine by molecular technologies for use in egg-type (layer hen) and potentially meat-type (broiler and turkey) production systems.

Approach:
A secondary vaccination with the F strain MG will be performed on layer chickens previously treated with the MG vaccines, ts-11 or 6/85. Efficacy of the secondary treatment will be determined and effects on layer hen productivity, physiology, and immunology will be quantitated. Effects of the secondary vaccination on eggs produced by treated layer hens will be investigated. The effect of MG vaccinations on B- and T-cell subpopulations will be determined via flow cytometry. Real-time RT-PCR will be used to determine changes in cytokine mRNA levels of interferon-gamma, interleukin-1, interleukin-6, interleukin-15, and interleukin-18 immediately preceding and following vaccinations. Transformation procedures will be developed for the commensal Mycoplasma gallinarum. Concurrently, surface proteins of M. gallinarum will be identified and their associative genes will be cloned. Putative MG genes (e.g. GapA and PvpA), will then be surface-expressed in recombinant strains of the M. gallinarum via protein fusions utilizing the C-terminal end of M. gallinarum surface proteins and the N-terminal end of MG antigens/colonization factors. The resulting recombinant M. gallinarum specie(s) will be evaluated for stability and pathogenicity, transmission, and protection against MG infection.

Project Team

Branton, Scott Evans, Jeff

Related National Programs

Animal Health (103)