Poster Presentation 8th Australasian Vaccines & Immunotherapeutics Development Meeting 2020

Polyethylenimine: an intranasal adjuvant for liposomal peptide-based subunit vaccine against group A Streptococcus (#304)

Charles C. Dai 1 , Jieru Yang 1 , Waleed M. Hussein 1 2 , Lili Zhao 1 , Xiumin Wang 1 3 4 , Zeinab G. Khalil 5 , Robert J. Capon 5 , Istvan Toth 1 5 6 , Rachel J. Stephenson 1
  1. School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
  2. Pharmaceutical Organic Chemistry Department, Faculty of Pharmacy, Helwan University, Helwan, Egypt
  3. Gene Engineering Laboratory, Feed Research Institute, Chinese Academy of Agricultural Sciences, Beijing, China
  4. Key Laboratory of Feed Biotechnology, Ministry of Agriculture and Rural Affairs, Beijing, China
  5. Institute for Molecular Biosciences, The University of Queensland, St Lucia, QLD, Australia
  6. School of Pharmacy, The University of Queensland, Woolloongabba, QLD, Australia

Group A Streptococcus (GAS) and its related diseases are global challenges, and they affect 34 million people worldwide with more than 345,000 deaths annually.1 However, there is currently no commercial or licensed GAS vaccines available. Vaccines have many routes of administration, including subcutaneous and intramuscular injection, or intranasal and oral delivery. Here, intranasal delivery has many benefits, including decreased needle-free and non-invasive administration and induction of the systemic and mucosal immunity inducing a rapid local and protective immune response.2

Polyethylenimine (PEI) is a hydrophilic cationic polymer, and PEI-coated nanoparticles, used as drug delivery systems, have been shown to promote the cellular uptake and improve the immune responses.3-5 In this study, we successfully demonstrated the development of PEI incorporated liposomes for the delivery of a lipopeptide-based vaccine against GAS. Outbred mice were administrated with the vaccine formulations intranasally with three boosts, and immunological investigation showed the PEI liposomes elicited both significant mucosal and systemic immunities with the production of IgA and IgG antibodies. Antibodies were shown to effectively opsonise multiple isolates of clinically isolated GAS from Australia. This proof-of-concept study showed the capability for PEI liposomes to act as a safe vehicle for the delivery of GAS peptide antigens to elicit immune responses against GAS infection, making PEI a promising addition to liposomal mucosal vaccines.

  1. Salehi, S. et al. mSphere 2018, 3(6), e00617-18.
  2. Marasini, N. et al. Ther Deliv 2017, 8(3), 151-167.
  3. Chen, X. et al. Mol Pharm, 2014, 11(6), 1772-1784.
  4. Salvador, A. et al. Int J Pharm, 2015, 496(2), 371-381.
  5. Yu, K. et al. Int J Pharm, 2016, 497(1-2), 78-87.