Rheological Characterization of 3D Printed Adipose Grafts for Wound Healing

Introduction: A revolutionary advance in personalized wound care uses a patient's own adipose tissue as the foundation for creating custom-designed wound tissue grafts with the Aplicor 3D printing system. By harnessing the power of additive manufacturing, the Aplicor 3D, an FDA-approved system, transforms processed autologous adipose tissue into a wound graft that is rich in growth factors. This study aims to characterize the rheological properties of these 3D printed grafts, particularly the storage modulus, the loss modulus, and the viscosity, as these are crucial parameters in predicting graft handling behavior during and after printing. Understanding these properties is critical to the clinical outcome as they can impact the graft’s stiffness, resistance to deformation, and ability to withstand physiological forces, thus affecting the ability of the grafts to retain its structure and function after implantation.Methods: Rheological properties of unprocessed (negative control) adipose, micronized adipose, and fibrinogen/thrombin gelled adipose tissue were assessed using a TA Instruments HR 20 Rheometer. Measurements were performed to study the flow and deformation of each material and to quantify the storage modulus, loss modulus, and viscosity. All testing was done under either frozen, room temperature, or body temperature conditions. Statistical analysis was performed to compare the rheological properties of all adipose tissue grafts.Results:Rheological measurements revealed a deeper understanding of the viscoelastic behavior of adipose tissue during printing and after grafts are formed. The properties and significant differences of the experimental grafts were compared against one other and a negative control (unprocessed adipose tissue).Discussion: These results provide insights into deformation and shearing forces of the ideal 3D printed autologous wound graft. It is important to understand these findings as they contribute to the optimization of 3D bioprinting parameters and, ultimately, the clinical efficacy of personalized adipose-derived wound grafts. References: