The Production and Delivery of Edible Plant- and Lactobacteria-derived Vaccines Dominic Man-Kit Lam Fung Hon Chu Endowed Chair of Humanics Hong Kong Baptist University WHO Meeting at HKBU 24 January 2013 Acknowledgements of Main Collaborators I. Edible Plants: Prof. Hugh Mason, Prof. Charles Arntzen, Dr. Jian Jian Shi, Dr. Yee Yee Lam, Dr. Fong Lam II. Lactobacteria: Dr. Han Lei, Prof. Yuhong Xu Expression of hepatitis B surface antigen in tomato fruit Expression of hepatitis B surface antigen in tomato fruit Genetic manipulation and plant breeding in Corn can boost expression 11 10 9 Cell 8 7 wall 6 targete 5 d Lt-B 4 3 2 1 0 T1 T2 T3 Seed generation Oral Vaccination for Swine TGEV With Edible Vaccines Produced in Corn The First Demonstration Of Vaccination With Edible Vaccines Advantages of lactic acid bacteria as mucosal-delivery vehicles 1. Lactic acid bacteria are generally regarded as safe (GRAS）, and are extensively used in fermented food products ； 2. Can survive passage through the stomach acid and contact with bile; 3. Fulfill the requirements of a delivery system in mucosal immunization; 4. The mucosal route of administration can potentially stimulate both system and mucosal immune responses, can elicit the production of secretory Ig A; 5. Are taken up to into Peyer’s patches, the inductive sites of the mucosal immune system; 6. Multiple antigens can be expressed in the same strain ； 7. Can be engineered to express targeting antigens and adjuvants; Wells, J.M. & Mercenier, A. Nature Rev Microbiol 2008, 6(5), 349-362. Fate of recombinant lactic acid bacteria in the intestinal tract Wells, J.M. & Mercenier, A. Nature Rev Microbiol 2008, 6(5), 349-362. H5N1 virus challenge experiment 100 80 60 PBS L.lactis (pNZ8110) L.lactis (pNZ8150-HA) 40 L.lactis (pNZ8110-HA) Percent survivalPercent L.lactis (pNZ8110-pgsA-HA1) PBS+CTB 20 L.lactis (pNZ8110)+CTB L.lactis (pNZ8150-HA)+CTB 0 L.lactis (pNZ8110-HA)+CTB L.lactis (pNZ8110-pgsA-HA1)+CTB 0 2 4 6 8 10 12 14 16 Days after infection Positive: percent survival＞60% Immune protection detected by H5N1 virus lethal challenges after oral deliveries of different vaccine preparations 5 mice/group Lei et al., 2011. Clinical and Vaccine Immunology 18(7): 1046-1051. H5N1 virus challenge experiment 100 80 60 PBS 40 L1 L2 Percentsurvival L3 L4 20 capsule-L1 capsule-L2 capsule-L3 capsule-L4 0 0 2 4 6 8 10 12 14 16 Days after infection Immune protection against H5N1 virus lethal challenges after oral deliveries of different vaccine preparations 5 mice/group; Positive: percent survival＞60%; Lei et al., 2010. Virology 407 (2): 319-324. HA A/duck/Anhui/1/06 (H5N1) HA A/Chicken/Shandong/6/96/ (H9N2) boost H9N2 H5N1(R-1) H5N1 (R-4) PBS （L1） 2.4±0.54772 2.4±0.47721 2.2±0.44721 H9N2 （L2） 8.2±0.44721 8.0±0.70711 8.2±0.44721 H5N1-M2 9.4±0.54721 8.0±0.70711 9.6±0.54772 （L4） H5N1-HA 9.0±0.70711 9.2±0.83666 9.4±0.54772 （L6） Potential Advantages of Edible Vaccines 1. Much lower costs of production 2. Safety --- no animal-related contaminants, no syringes and needles used 3. Higher stability (e.g. proteins in seeds can be preserved for years even at room temp.) 4. Easier compliance, especially for multi-dose vaccinations --- Vaccines can be kept and administrated orally at home 5. Cost-effective and easier administration of vaccines for animals (livestock, pets etc.) 6. Especially suitable for less developed countries or regions. Edible Vaccines For Animals Edible Vaccines For Human .