Research/Mycoplasma vaccines
From Poultry Hub
Title: Mycoplasma vaccines
Project Leader: Philip Markham at University of Melbourne, University of Sydney and Bioproperties funded by Poultry CRC (Project 03-11)
Duration of Project: Now completed (1 January 2004 to 31 July 2008)
Contents |
Project overview
Mycoplasma gallisepticum (MG) causes chronic respiratory disease (CRD) in poultry worldwide. The current method used to control CRD in Australia relies on vaccination with the live attenuated MG strain ts-11. Confidence in a successful vaccine take is hampered by poor antibody response and differentiation of the vaccine from field strains. There is also potential to capitalise on its ability to express foreign antigens and produce a vaccine vector.
Project objectives
- Develop and improve serological based tests to detect vaccination status of poultry
- Produce serologically identifiable attenuated Mycoplasma vaccines
- Develop MG vaccine strain ts-11 as a vaccine vector
- Determine virulence genes in MG
Project progress
This project is now completed and a final report will soon be available from the Poultry CRC.
The project team developed expression vectors and systems for Mycoplasma gallisepticum and identified a number of attenuating genes in Mycoplasma gallisepticum. The potential to develop bacterial vaccines using specific gene knockouts (identified in M. gallisepticum) was extended to avian pathogenic Escherichia coli. Two gene knockouts strains were developed. One gene knockout strain was attenuated in chickens compared to the parent wild type. This will form the basis of patentable methodology for producing vaccines. The second part of the research developed a system to express foreign proteins on the cell surface of M. gallisepticum using laboratory developed vectors to introduce and express chicken gamma interferon and genetic markers in the vaccine strain MG ts-11.
