150 likes | 413 Views
Edible Vaccines: eating our way to the eradication of disease. Vaccines. Eradication of small-pox Vaccine preventable diseases millions of deaths per year No vaccines HIV; ~2 million deaths per year malaria; 1.5 - 2.7 million deaths per year.
E N D
Edible Vaccines:eating our way to the eradication of disease
Vaccines • Eradication of small-pox • Vaccine preventable diseases • millions of deaths per year • No vaccines • HIV; ~2 million deaths per year • malaria; 1.5 - 2.7 million deaths per year There is a clear need for new vaccines, and vaccination strategies
Why is measles still killing children? • Failure to vaccinate: • fear • safety and side effects • misconceptions • prevalence and seriousness • access/availability • Vaccine failure: • inactivation by heat • interference by maternal antibodies
A subunit based edible vaccine? • economical • heat stable • oral administration • no more needles • mucosal immune response • sub-unit vaccine • unable to replicate • overcome maternal antibodies
H P F L RNA + N M Developing an edible vaccine for measles • select an antigen • Hemagglutinin (H) protein • surface exposed protein • targeted during the immune response • sufficient to induce protective immunity
Tobacco expressing the MV-H protein MV-H control - + - + PNGase F 100kDa 75kDa 50kDa Transgenic tobacco Western blot
Feeding tobacco may also induce a mucosal immune response titre Naive MV-H Control Treatment groups
From model system to practical vaccine • Edible species tobacco lettuce control rice control 75kDa MV-H 50kDa
From model system to practical vaccine • Edible species – intraperitoneal experiment MV-specific serum IgG titers MV-H tobacco MV-H lettuce control lettuce
From model system to practical vaccine • Edible species – intraperitoneal experiment MV-neutralisation titers control lettuce MV-H lettuce
From model system to practical vaccine • an edible species • delivery and dose issues • quantity and number • higher antigen expression in plants • targeting the antigen for better uptake • safety issues • quality control and licensing • GMO issues
Summary: • tobacco, lettuce and rice can express the MV-H protein • plant-derived MV-H protein is able to induce MV neutralising antibodies in mice • edible vaccines have the potential to address the limitations of the current measles vaccine
Acknowledgements CSIRO, Adelaide Ian Dry Terri King Steve Choimes Viral Vaccine Unit, (Monash University) Steve Wesselingh Jenny Martin Diane Webster Michelle Cooney Zhongjun Huang Melbourne University Richard Strugnell