Exosomes in nanomedicine: a promising cell-free therapeutic intervention in burn wounds

Abstract

Burn injuries are serious injuries that have a big impact on a person's health and can even cause death. Incurring severe burns can incite an immune response and inflammation within the body, alongside metabolic changes. It is of utmost importance to grasp the fact that the effects of the burn injury extend beyond the body, affecting the mind and overall well-being. Burn injuries cause long-lasting changes that need to be taken care of in order to improve their quality of life. The intricate process of skin regeneration at the site of a burn wound involves a complex and dynamic interplay among diverse cells, growth factors, nerves, and blood vessels. Exciting opportunities have arisen in the field of stem cells and regenerative medicine, allowing us to explore the development of cell-free-based alternatives that can aid in the treatment of burn injuries. These cell-free-based therapies have emerged as a promising facet within regenerative medicine. Exosomes, also referred to as naturally occurring nanoparticles, are small endosome-derived vesicles that facilitate the delivery of molecular cargo between the cells, thus allowing intercellular communication. The knowledge gained in this field has continued to support their therapeutic potential, particularly in the domains of wound healing and tissue regeneration. Notably, exosomes derived from mesenchymal stem cells (MSCs) can be safely administered in the system, which is then adeptly uptaken and internalized by fibroblasts/epithelial cells, subsequently accelerating essential processes such as migration, proliferation, and collagen synthesis. Furthermore, exosomes released by immune cells, specifically macrophages, possess the capability to modulate inflammation and effectively diminish it in adjacent cells. Exosomes also act as carriers when integrated with a scaffold, leading to scarless healing of cutaneous wounds. This comprehensive review examines the role of exosomes in burn wound healing and their potential utility in regeneration and repair.

Keywords: Angiogenesis; Burns; Exosomes; Extracellular vesicles; Inflammation; miRNA.

Fig. 1

Classification of burn wounds on the basis of severity of damage to the skin

Fig. 2

Stages of burn wound healing: (1) Inflammatory Response: pro-inflammatory macrophages clear the wound from bacterial infection (2) Immune Recruitment: neutrophils and monocytes provide signal molecules important for wound healing (3) Healed wound: construction of granulation tissue contracts the wound

Fig. 3

Conventional methods of burn wound management

Fig. 4

Structure and composition of exosomes. The exosome comprises a phospholipid bilayer membrane. The composition of exosomes is influenced by the host’s health, the cell type from which it is obtained, and external stimuli. The proteins annexins, tetraspanins, Alix, TSG101, MHC molecules, Rab proteins, cytoskeletal proteins, enzymes, growth factors, cytokines, and signal transduction proteins are all found in exosomes along with miRNA, mRNA, DNA and other molecules

Fig. 5

Role of exosomes on the skin and wound healing