Microprojection arrays applied to skin generate mechanical stress, induce an inflammatory transcriptome and cell death, and improve vaccine-induced immune responses.

Chemical adjuvants are typically used to improve immune responses induced by immunisation with protein antigens. Here we demonstrate an approach to enhance immune responses that does not require chemical adjuvants. We applied microprojection arrays to the skin, producing a range of controlled mechanical energy to invoke localised inflammation, while administering influenza split virus protein antigen.

Potent response of QS-21 as a vaccine adjuvant in the skin when delivered with the Nanopatch, resulted in adjuvant dose sparing.

Adjuvants play a key role in boosting immunogenicity of vaccines, particularly for subunit protein vaccines. In this study we investigated the induction of antibody response against trivalent influenza subunit protein antigen and a saponin adjuvant, QS-21. Clinical trials of QS-21 have demonstrated the safety but, also a need of high dose for optimal immunity, which could possibly reduce patient acceptability.

Influenza nucleoprotein DNA vaccination by a skin targeted, dry coated, densely packed microprojection array (Nanopatch) induces potent antibody and CD8(+) T cell responses.

DNA vaccines have many advantages such as thermostability and the ease and rapidity of manufacture; for example, in an influenza pandemic situation where rapid production of vaccine is essential. However, immunogenicity of DNA vaccines was shown to be poor in humans unless large doses of DNA are used. If a highly efficacious DNA vaccine delivery system could be identified, then DNA vaccines have the potential to displace protein vaccines.

Induction of potent CD8⁺ T cell responses through the delivery of subunit protein vaccines to skin antigen-presenting cells using densely packed microprojection arrays.

The generation of both antibody and CD8⁺ T cell responses against pathogens is considered important for many advanced vaccines for diseases including tuberculosis, HIV and malaria. However, most current vaccines are delivered into muscle by the needle and syringe method and induce protection via humoral (antibody) immune responses. In this paper, we test the hypothesis that delivering a model subunit protein antigen (ovalbumin) to the skin's abundant immune cell population using a densely packed microprojection array (Nanopatch) enhances CD8⁺ T cell responses.