The Importance of Nanocarrier Design and Composition for an Efficient Nanoparticle-Mediated Transdermal Vaccination

Abstract

The World Health Organization estimates that the pandemic caused by the SARS-CoV-2 virus claimed more than 3 million lives in 2020 alone. This situation has highlighted the importance of vaccination programs and the urgency of working on new technologies that allow an efficient, safe, and effective immunization. From this perspective, nanomedicine has provided novel tools for the design of the new generation of vaccines. Among the challenges of the new vaccine generations is the search for alternative routes of antigen delivery due to costs, risks, need for trained personnel, and low acceptance in the population associated with the parenteral route. Along these lines, transdermal immunization has been raised as a promising alternative for antigen delivery and vaccination based on a large absorption surface and an abundance of immune system cells. These features contribute to a high barrier capacity and high immunological efficiency for transdermal immunization. However, the stratum corneum barrier constitutes a significant challenge for generating new pharmaceutical forms for transdermal antigen delivery. This review addresses the biological bases for transdermal immunomodulation and the technological advances in the field of nanomedicine, from the passage of antigens facilitated by devices to cross the stratum corneum, to the design of nanosystems, with an emphasis on the importance of design and composition towards the new generation of needle-free nanometric transdermal systems.

Non-invasive transcutaneous influenza immunization using vaccine-loaded vaterite particles

“…Various nano-and microparticles are of great interest in topical vaccine delivery. 17,38,39 Their use in vaccine formulations allows for improved stability and targeted delivery of the antigen as well as enabling its in situ release. As mentioned above, the transfollicular route was highlighted as a perspective delivery pathway for particulate formulations into the skin.…”

Beneath the Skin: A Review of Current Trends and Future Prospects of Transdermal Drug Delivery Systems

“…Lastly, NPs can be delivered through various routes of administration that may achieve site-specific drug delivery [170]. NPs have been studied for application in the transdermal delivery of vaccines [171], anti-hypertensives [172], anti-cancer agents [173], and many other drugs [174]. NPs are generally classified into three types: organic (polymeric), inorganic, and carbon-based NPs [166] (Figure 6).…”

Poly(β-amino ester)s-Based Delivery Systems for Targeted Transdermal Vaccination

“…The skin, being an immune sentry-rich tissue, has been proposed as a superior route for immunization over the intramuscular since it hosts a profoundly richer network of antigen-presenting cells (APCs) contributing to the immunocompetence of the skin [7,8]. However, the first-generation of transdermal vaccines proved to be poorly immunogenic in humans due to inefficient gene delivery and weak cell transfection [9], evidencing the need for more refined delivery vectors to enhance immunization levels [10,11]. Poly(β-amino ester)s (PBAEs) are highly regarded delivery vectors due to their excellent biocompatibility, biodegradability, and an ease of synthesis without solvents nor catalysts [12][13][14].…”