11/15/2024
By Zhiyong Gu
Dr. Su Ryon Shin, Assistant Professor of Medicine, Brigham and Women’s Hospital, Harvard Medical School, gives a Chemical Engineering seminar titled, "Engineering nano-biomaterials for regenerative medicine and biohybrid actuators."
Time: Thursday, Nov. 21, 3:30 to 4:45 p.m.
Location: Shah Hall 301
Abstract: Recapitulating inherent heterogeneity and complex microarchitectures of native tissues for developing clinically relevant three-dimensional (3D) tissues or organs has emerged as a potential solution for tissue regeneration. Recently, advanced microfabrication technologies and functional biomaterials have been developed to create biomimetic tissue constructs and to mimic the functional behaviors of native tissues. However, several significant challenges in tissue engineering still exist, such as recapitulating the in vitro, 3D hierarchical microarchitecture comprised of multiple cell types and the extracellular matrix (ECM) components of native tissues and achieving the continuous function and viability of engineered tissues after implantation. To do this, we developed an advanced multi-material bioprinting platform that employs self-healing ECM-like supporting baths and a programmable microfluidic device, which can quickly switch between different materials, biological reagents, and cells. The self-healing ECM-like colloidal gels can physically support soft 3D printed constructs to maintain their complex geometries while enabling rapid cell infiltration and vascularization in vivo. This advanced bioprinting platform allowed us to fabricate complex geometrical structures such as centimeter scale pre-vascularized 3D skeletal muscle tissue constructs and skeletal muscle connective tissue (MCT)-layered myofibers through the development of stem cell fate-controlling biomaterials that achieve both myogenesis and fibroblast differentiation in a locally controlled manner at the single construct. Another challenge is the survival of bioprinted 3D tissue constructs at the injured area, which is fully dependent on the oxygenation derived by its connection to the blood circulation of the host body. Incorporating functional biomaterials (i.e., oxygenating micromaterials) into cell-laden 3D constructs could solve these problems, as it immediately allows for oxygen delivery. Therefore, we have developed oxygenating micromaterials containing molecules that release oxygen upon hydrolysis over a duration of two weeks, allowing the implant to survive its non-perfused phase and enabling the continued functioning of living implants. We recently observed promising results that showed mesenchymal stem cell (MSC)-laden oxygenating hydrogels to improve angiogenic factor secretion and vessel formation in vivo significantly. Self-oxygenation of tissues thus represents a novel, effective, and widely applicable strategy to enable the vascularization of living implants, which is expected to advance organ transplantation and regenerative medicine applications.
Dr. Su Ryon Shin is an Assistant Professor and Principal Investigator of Medicine at Brigham and Women's Hospital, Harvard Medical School. Dr. Shin received a doctoral degree from Hanyang University, South Korea. In Nov. 2010, she joined Prof. Ali Khademhosseini's group at Brigham and Women's Hospital, Harvard Medical School, Harvard-MIT Division of Health Sciences and Technologies, and Wyss Institute for Biologically Inspired Engineering as a postdoctoral research fellow. Dr. Shin is an expert in the field of nanomaterials, biomaterials, tissue engineering, electrochemical actuator, biosensor, organ-on-a-chip, and 3D bioprinting.