In Vitro Composite 3D Bioprinted Bone/Skin Constructs

Restricted (Penn State Only)
Author:
Godzik, Kevin Powers
Area of Honors:
Biomedical Engineering
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
  • Ibrahim Tarik Ozbolat, Thesis Supervisor
  • Justin Lee Brown, Honors Advisor
Keywords:
  • bioprinting
  • biomaterial
  • 3d printing
  • additive manufacturing
  • Co-culture
  • bone
  • skin
Abstract:
Of the tissues that make up the human body, bone and skin remain the most in demand due to the pervasiveness of skin lesions, chronic wounds, and osteoporosis-related issues. Congenital and acquired craniofacial abnormalities also require use and understanding of these two tissue types for comprehensive reconstruction of the affected areas. The variety and complexity of such complications makes craniofacial reconstruction expensive and time-consuming. The formulation and administration of novel biomaterials is necessary to combat these ever-growing needs. Technologies such as three-dimensional (3D) bioprinting—the deposition of biologically conducive or inductive materials using prescribed toolpaths generated from 3D models—are expanding ways biomaterials are processed and can interact with the body. However, as the intricacy of these materials increases, it is vital to understand the interactions between them. As such, novel hydrogel-based rat bone mesenchymal stem cell (rBMSC)-laden bone and rat dermal fibroblast (RDF)-laden skin 3D-printable bioinks were developed to stimulate the recovery of the tissues, bioprinted, and characterized in order to determine their in vitro response. Cell proliferation assays showed no decrease in proliferation rate for directly cocultured samples. Enhanced fibrogenesis in and morphology of direct-contact cocultured constructs was observed using SEM and gene expression for both groups was quantified using RT-qPCR (using markers for runt-related transcription factor 2 (RUNX2), collagen type I (COL), and alkaline phosphatase (ALP)). In conclusion, a novel way to culture and study the interface of composite bioprinted constructs is proposed in order to further study the complex interactions of proximate cell-laden biomaterials in vitro with craniofacial reconstruction in mind.