Towards the design of universal influenza vaccines, our proposal involves (1) novel resurfacing neuraminidase (NA) antigen(s) of pH1N1 influenza A virus using mutations or N-glycan masking/unmasking design to refocus antibody response to the most cross-reactive NA epitopes to expand the breadth of current vaccines; (2) structure-based design to determine the relationship between structural and antigenic integrity of novel of type II heat labile enterotoxin (LTIIb) mucosal adjuvants and NA/LTIIb-fusion proteins to modulate its effect on the downstream receptors. Three approaches will be considered here, including site-directed mutagenesis, artificial LTIIb monomer design and de novo protein chimera. We hope to have new designs with less GD1a binding ability, sufficient TLR-2/1 affinity to trigger immune response and minimized cell toxicity; (3) squalene-based nanoemulsion production at pilot scale will be accomplished by homogenization with a high-pressure homogenizer. We plan to optimize a safe and effective adjuvant combination system using co-administrating nanoemulsion together with LTIIb-A protein or LTIIb-B protein chimera. The overall research project allows the integration of virology, immunology, structural model, and material science to facilitate the development of universal influenza vaccine and formulations for the induction of broadened and appropriate immune responses. We will also launch a mechanistic study to address how nasal mucosal membrane interacts with the optimal vaccine at molecular and cellular level and to elucidate the impact of antigen/adjuvant structure on the protection against virus challenges following intranasal delivery of a universal influenza vaccine. Immunological study will also be conducted to investigate the modulation of the immune microenvironments at local vaccination tissues and ipsilateral draining lymph nodes, thereby synergistically integrating the vaccine efficacy. Finally, we will investigate the histological examination of the tissue or organ integrities and monitor the serum biochemistry to study the biocompatibility of combination adjuvants in mice, and study whether combination adjuvants can turn on the autoimmune diseases. These results pave the way for a universal vaccine against influenza illness.