Current methods of vaccination primarily rely on intramuscular, subcutaneous, and intradermal injection of antigens. These vaccination routes, while effective, require medical personnel to deliver, generate biohazards (sharps) requiring costly disposal, and cause patients pain and anxiety.
This has fueled research efforts to identify “needle-free” methods of immunization. However, the skin has a protective barrier against the external environment, making the trans‑dermal delivery of active macro molecules very difficult.
A number of epicutaneous vaccine delivery systems have been explored, including electroporation and microneedle-based techniques. Unfortunately, electroporation of antigens into the skin requires expensive machinery and microneedles suffer from inadequate antigen loading, poor reproducibility, incomplete dissolution of microneedles, and costly manufacturing.
Researchers at the University of Rochester have identified a number of synthetic peptides that inhibit the formation of tight junctions (TJs). These sequences are entirely artificial and have no homology with known, naturally-occurring peptides or proteins.
TJs are the Velcro-like connections between cells in epithelial layers, serving as a physical barrier to paracellular transport of large molecules. When treated with the UR proprietary TJ-targeting peptides, this barrier is temporarily disrupted.
In vitro data demonstrates transport of molecules as large as monoclonal antibodies across model epithelium, and in vivo data indicate transdermal delivery of vaccine antigens.