New prospects for vaccination: from polio to dengue and flu

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1 New prospects for vaccination: from polio to dengue and flu From ancient Chinese variolation to Jenner and cowpox Paul Young Australian Infectious Diseases Research Centre School of Chemistry and Molecular Biosciences

2 Modern vaccines ACTIVE INACTIVATED - under conditions that retain immunogenic properties ATTENUATED - virulent organism weakened by growth in unnatural host PASSIVE Instilling the products of the immune response (antibodies or immune cells) into the recipient only useful for short term protection, e.g., rabies immune globulin Prime objective of a vaccine stimulated immune response is to protect against disease - not necessarily prevent infection

3 Vaccines have an excellent track record Smallpox Yellow fever Polio Measles Disease heat maps

4 Active vaccines ADJUVANTS stimulate immune response DELIVERY route can define quality and type of immune response

5 Active vaccines inactivated polio virus IPV ADJUVANTS stimulate immune response DELIVERY route can define quality and type of immune response Nanopatch Dengue and Influenza

6 Successful subunit vaccines Influenza virus virus grown in eggs, purified and disrupted into immunogenic component Hepatitis B virus (HBV) HBsAg produced recombinantly in yeast Human papillomavirus (HPV) Gardasil (Merck): types 6, 11, 16, 18 produced in S. cerevisiae Cervarix (GlaxoSmithKline): types 45, 31 produced in insect cells + AS04 (aluminium hydroxide and 3-Odesacyl-4 -monophosphoryl lipid A)

7 Dengue virus Envelope (E) protein 5 C prm E NS1 NS2A NS2B NS3 NS4A Flavivirus NS4B structure NS5 3 Envelope 5'- furin prm! pr+m NC ns2a ns2b ns4a ns4b C prm E NS1 NS3 NS5 Protease/Helicase Polym Biological properties 3 structural domains Domain 1 (red) Domain 2 (yellow) Domain 3 (blue) E glycoprotein biology o Target of neutralizing antibody response o o o Vaccine candidate Contains viral fusion peptide and receptor binding motif Kuhn et al., 2002 Major virion surface protein Induces virus-neutralizing/protective antibody Involved in virus attachment Mediates virus-specific membrane fusion NS-proteins (NS3) elicits cytotoxic T-cell response 7

8 Subunit vaccine 80% E protein (se) produced in S2 cells: Den 1: Den 2: PR159 Den 3: CH53489 Den 4: H241 Key target for neutralising antibody Balance immune response by varying antigen concentration Subunit vaccine suffer from poor immunogenicity Dengue virus E se 8

9 The Nanopatch High density microprojection arrays >20,000 microprojections/cm 2 9

10 Correlation between cell death and immunogenicity Dynamic application of the Nanopatch generates localized transient stresses invoking cell death around each projection. Depelsenaire et al. (2014) Journal of Investigative Dermatology, April 2014; doi: /jid

11 Dose sparing Adapted from Fernando et al. (2010) PLoS ONE

12 Aims Evaluate the antibody responses to tetravalent dengue se vaccination: Investigating different delivery methods Demonstrate the protective efficacy of Nanopatch delivered se in a lethal challenge model. Monitoring viral load, NS1 levels and survival

13 Nanopatch delivery of se

14 SV129 Dose ranging experiment Aim: To determine the best route of immunization to elicit potent anti-se IgG SV129 mice: parental background to AG129 dengue model Dose 1 Dose 2 Dose 3 day

15 se immune responses NP immunization with Quil A produces significantly more anti-se IgG than all other delivery methods

16 AG129 dengue challenge study Small animal model for dengue virus infection Interferon α, β and γ receptor knockouts Dose 1 Dose 2 Dose 3 challenge day

17 Results: Anti-sE IgG response

18 Survival to lethal challenge

19 Nanopatch can deliver dengue virus se antigen Saponin adjuvant QuilA enhances antibody titres Enhanced immune response to the four dengue serotypes Elicits balanced neutralising antibody response Anti-sE reponses in AG129 mice were protective to lethal challenge

20 SEM - uncoated Nanopatch microsphere depth in skin fluorescent microspheres deposited into the ear Cryo SEM of Nanopatch projections in place within the viable epidermal and dermal layers of ear skin.

21 Dose-sparing and efficient one dose response

22 Nanopatch: Features and Benefits Key Features: Immune enhancer Dose sparing Adjuvant sparing Thermostability Versatility Scalable manufacturing Key Benefits: No needles Less discomfort than needles Improved immunogenicity No cold-chain 22

23 Viral fusion proteins Process of membrane fusion is driven by conformational change in structure of the virion surface fusion protein Pre-fusion Post-fusion Potent neutralizing Abs target the pre-fusion form

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25 Evidence for pre-fusion stabilization for a range of viral fusion proteins

26 Influenza HA Clamp

27 The Future? Synthetic peptides DNA vaccines (DNA launched virus vaccines) Improved adjuvants, liposomes, ISCOMS etc Edible vaccines transgenic plants - algae New delivery methods eg Nanopatches Prof Mark Kendall

28 Acknowledgements PRY Lab Keith Chappell Daniel Watterson David Muller Vernon Seow Naphak Modhiran Sue Liebscher Ashleigh Shannon Imogen Bermingham Jaelle Brealey Stacey Cheung Andrew Young Chris McMillan Stradbroke Island retreat Jan 2015 Mark Kendall, UQ Vaxxas WHO