MAFF tuberculosis vaccines for animals research programme
Report by programme advisor for the period 1 July 1999 to 30 June 2000
Dr MJ Colston, Head, Division of Mycobacterial Research, The National Institute for Medical Research, London NW7 1AA
Contents
- Strategy
- Research Contracts
- Progress and comments
- MAff TB vaccine research
- starting 01/04/99
- starting prior to 01/04/99
Strategy
The overall strategy for vaccine development is summarised in Figure 1. The major focus of the Programme involves the development of a vaccine for use in cattle, although the option of developing a vaccine for badgers is being retained. In Figure 1 the cattle/badger strategy is shown alongside a strategy for the development of a human tuberculosis vaccine. The initial approach of developing vaccine candidates is similar irrespective of the ultimate target species.
The types of vaccine candidates being investigated fall into two broad categories:- subunit vaccines and live, attenuated mycobacterial vaccines (Figure 2). Subunit vaccines may consist of recombinant proteins and/or other immunogenic molecules (glycoproteins, lipoproteins, etc.), or nucleic acid based vaccines. Attenuated mycobacterial vaccines are generally likely to consist of strains of M.bovis in which a particular gene, or genes has been specifically deleted rendering the M.bovis unable to produce disease but able to generate an immune response against the normal, unmutated pathogen.
The initial testing of these candidate vaccines is carried out in laboratory animal models, initially mice and subsequently guinea pigs. A unique feature of the cattle vaccine programme is that candidate vaccines which show promise in the mice/guinea pigs screen can then be tested in the natural host species, cattle, before progressing towards clinical trials. This is a major advantage over the strategy for developing a vaccine for human tuberculosis, where, of course, it is impossible to test a candidate vaccine by experimentally challenging the host species with the pathogen. In principle, a potential badger vaccine could also be tested in infectious challenge experiments carried out in the targetted host species (the badger). If a badger vaccine is to be retained as an option, the possible use of experimentally infected badgers needs to be investigated.
Page last modified:
12 August 2003
Page published: 5 February 2003