PhD ceremony Ms. H. Liu: Improvement of influenza vaccines by using a saponin-derived adjuvant

PhD ceremony: Ms. H. Liu, 11.00 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: Improvement of influenza vaccines by using a saponin-derived adjuvant

Promotor(s): prof. A.L.W. Huckriede, prof. J.C. Wilschut

Faculty: Medical Sciences

Effective influenza vaccines should protect individuals from influenza infection and reduce the socio-economic burden imposed by the disease. Current influenza vaccines, however, show only partial efficacy and effectiveness in healthy adults. Moreover, proof of satisfactory protection among small children and the elderly, the most vulnerable populations for influenza infection, is still lacking. In this thesis, we show that the immunogenicity and protective capacity of influenza vaccines can be significantly potentiated by the incorporation of the adjuvant GPI-0100 in the vaccine. GPI-0100 is a molecule from the bark of the soap bark tree Quillaja saponaria. In mice, influenza vaccines containing GPI-0100 elicit significantly improved immune responses of higher magnitude and better quality, when compared to those induced by the same vaccines without GPI-0100. Importantly, substantial protection of the lungs can be achieved by vaccination with GPI-0100-containing influenza vaccines at an extremely low antigen dose. This can be particularly beneficial during pandemics when vaccine demand is huge, but antigen supply limited. Therefore, GPI-0100 can help to overcome the limitations concerning immunogenicity and availability of current influenza vaccines. We also show that the performance of GPI-0100-adjuvanted influenza vaccine can be further improved by choosing an optimal antigen formulation (e.g., reconstituted viral envelopes) and route of vaccine administration (e.g., pulmonary immunisation).