Mucosal Delivery of HA-Stalk Focused Vaccine Using Lactobacillus to Induce Broadly Cross Protection Against Swine Influenza Infections

Swine flu caused by influenza viruses is an important disease for the pork industry. Vaccination is an effective approach for preventing swine flu epidemic and reducing economic loss. However, current commercial available swine flu vaccines in the US are using killed or inactivated whole swine flu viruses which can easily become less effective due to virus mutations. This research project has used protein structure based approaches to design a chimeric antigen which can induce a robust immune response targeting viral conserved sites so that it can be more effective against a variety of swine flu strains. Furthermore, this vaccine will be produced and delivered using live lactic acid bacteria (LAB) so that it can act at the mucosal surface (port-of-viral entry). Therefore, this new type of vaccine we are developing is a fundamentally different vaccine. The advantages of this Lactobacillus based recombinant vaccine can be summarized as follows: 1). mucosal surface based vaccination; 2). cost-effective for producing the vaccines; 3). easy to use, oral or intranasal inoculation, no injections. In this proof-of-concept research, our preliminary data showed that this bacteria based vaccine appeared to be comparable to the current commercial vaccine tested.