Synthetic Skin-Permeable Proteins Enabling Needleless Immunization

Nanocarriers for Skin Applications: Where Do We Stand?

Skin penetration of active molecules for treatment of diverse diseases is a major field of research owing to the advantages associated with the skin like easy accessibility, reduced systemic-derived side effects, and increased therapeutic efficacy. Despite these advantages, dermal drug delivery is generally challenging due to the low skin permeability of therapeutics. Although various methods have been developed to improve skin penetration and permeation of therapeutics, they are usually aggressive and could lead to irreversible damage to the stratum corneum. Nanosized carrier systems represent an alternative approach for current technologies, with minimal damage to the natural barrier function of skin. In this Review, the use of nanoparticles to deliver drug molecules, genetic material, and vaccines into the skin is discussed. In addition, nanotoxicology studies and the recent clinical development of nanoparticles are highlighted to shed light on their potential to undergo market translation.

Polymeric nanocapsules: a potential new therapy for corneal wound healing

Corneal injuries are one of the most frequently observed ocular diseases, leading to permanent damage and impaired vision if they are not treated properly. In this sense, adequate wound healing after injury is critical for keeping the integrity and structure of the cornea. The goal of this work was to assess the potential of polymeric nanocapsules, either unloaded or loaded with cyclosporine A or vitamin A, alone or in combination with mitomycin C, for the treatment of corneal injuries induced by photorefractive keratectomy surgery. The biopolymers selected for the formation of the nanocapsules were polyarginine and protamine, which are known for their penetration enhancement effect. The results showed that, following topical instillation to a mouse model of corneal injury, all the nanocapsule formulations, either unloaded or loaded with cyclosporine A or vitamin A, were able to stimulate corneal wound healing. In addition, the healing rate observed for the combination of unloaded protamine nanocapsules with mitomycin C was comparable to the one observed for the positive control Cacicol®, a biopolymer known as a corneal wound healing enhancer. Regarding the corneal opacity, the initial grade of corneal haze (>3) induced by the photorefractive keratectomy was more rapidly reduced in the case of the positive control, Cacicol®, than in corneas treated with the nanocapsules. In conclusion, this work shows that drug-free arginine-rich (polyarginine, protamine) nanocapsules exhibit a positive behavior with regard to their potential use for corneal wound healing.

Polymer nanomicelles for efficient mucus delivery and antigen-specific high mucosal immunity

Micelles for mucosal immunity: A mucosal vaccine system based on γ-PGA nanomicelles and viral antigens was synthesized. The intranasal administration of the vaccine system induces a high immune response both in the humoral and cellular immunity (see picture).