Healing without scars: blood-based scaffolds for chronic wounds
Researchers have successfully used blood-based scaffolds to optimize wound healing in mice with chronic skin damage.
A research team, led by Joo Kang of the Ulsan Institute of Science & Technology (South Korea), has recently developed a technology that is able to generate artificial tissue scaffolds with microcapillary networks. These scaffolds optimize wound healing without scarification and could form future treatment options that address some of the complications with natural wound healing.
Chronic wounds often fail to heal properly, which presents complications that are associated with diabetes, vascular diseases and in severe cases, life-threatening sepsis. The use of artificial tissue scaffolds in wound healing is not new, but previous methods that use cell-laden hydrogel patches with adipose tissue or platelet-rich plasma are not capable of developing robust microcapillary networks, which are crucial to wound healing. They are also incapable of generating a uniform vasculature in a scalable manner.
To address this limitation, Kang’s team developed tissue scaffolds, called implantable vascularized engineered thrombi (IVETs). They manipulated microfluidic sheer stresses to align bundled fibers of fibrin with the direction of blood flow streamlines while activating platelets. This results in a microenvironment stiffness that is optimal for endothelial cell maturation and vascularization, enhancing wound healing. Furthermore, the IVETs were generated with autologous sources of blood, which maintains the compatibility of the scaffold with the patient.
Growing skin grafts in three dimensions
Bioengineers from Columbia University (NY, USA) have developed a method for creating 3D bioengineered skin grafts.
With the implantation of these IVETs to chronic skin wounds in mice, they observed superior wound closure rates, increased epidermis thickness, enhanced collagen deposition, hair-cell regeneration, reduced neutrophil infiltration and accelerated wound healing through improved microvascular circulation. The team also tested the efficacy of the IVETs by introducing methicillin-resistant Staphylococcus aureus to the site of skin damage. Alongside enhanced wound healing and vascularisation, the IVET facilitated enhanced migration of M2 phenotype macrophages, immune cells that combat bacterial infection.
Given further development and refinement, this technology could pave the way for the use of autologous blood-derived tissue scaffolding in chronic skin wounds, with further application in the regeneration of different tissue types.