Discipline: Biological Sciences
Subcategory: Microbiology/Immunology/Virology
Terrell Hilliard - Alabama State University
Co-Author(s): Vinoy Thomas, University of Alabama Birmingham, Birmingham, Alabama; Derrick Dean, Alabama State University, Montgomery, Alabama; Shree Singh,Alabama State University, Montgomery, Alabama; Vida Dennis, Alabama State University, Montgomery, Alabama
Wound healing is a natural but complex process involving morbidities such as burns and deep-tissue damage which results in slow or complete loss of regeneration. Autografts are the preferred method of repair but are insufficient in severe cases. Skin graft substitutes are now providing significant improvements over traditional allografts. Keratinocytes play a pivotal role by proliferating and differentiating to restore the barrier and allowing re-epithelialization. Herein, we developed a 3D wound healing model that supports wound healing and accelerates the process. A pre-established keratinocyte COCA cell line derived from the epidermis of mice was used as a skin substitute layer, grown for 2 weeks’ post differentiation in a 3D air-lift scaffold culture system with biomaterials (collagen, chitosan, naringenin, antimicrobial peptides) and analyzed for wound healing assessment. We hypothesized that biomaterials would enhance and accelerate wound healing. Wounds incisions were introduced onto the layer of 3D air-lift cultures by sharp scalpel and incubated for different time-points and visualized microscopically daily up to 20 days. Wound healing was evaluated by the reduction of gap incisions as compared with untreated cultures. To further improve wound healing, we exploited the regenerative properties of 3D scaffolds made of the biodegradable and biocompatible polymer Poly-L-lactic acid (PLLA). Since porous structures can promote rapid healing, we hypothesized that the chemical composition and architecture of the 3D scaffold could rapidly affect the proliferation and differentiation of new skin tissues. The microfiber scaffolds were generated using wet-laid technique containing high molecular weight chitosan which is ideal for promoting wound healing as it possesses multifaceted biological properties. Additionally, purified type I collagen was utilized to give additional strength and elasticity to scaffolds and genipin was included as a natural biocompatible water-soluble cross-linker. Scaffolds were characterized using scanning electron microscopy to view their morphology at the microscopic level. Fourier transform infrared spectroscopy was used to determine the functional groups present in scaffolds; differential scanning calorimetry was used to determine thermal stability, and a tensile strength test was carried out using the RSA-G2 solids analyzer to determine the overall durability of scaffolds. Our results show that PLLA and biomaterials significantly reduced wound incisions by promoting the continuous growth and differentiation of keratinocytes. Our advanced 3D polymeric skin model showed that the biomaterials provided continuous benefits to the cells for regeneration and were efficacious in accelerating wound healing.
Not SubmittedFunder Acknowledgement(s): This work was supported by funding from National Institutes of Health-NIGMS-RISE (1R25GM106995-01), NSF-CREST (HRD-1241701), NSF-HBCU-RISE (HRD-1646729
Faculty Advisor: Dr. Vida Dennis, vdennis@alasu.edu
Role: I completed all of the research