3D Printing of Organs: Are we there yet?

Wednesday, March 27, 2019 at 7 PM
CLU Gilbert Sports and Fitness Center, 130 Overton Court, rooms 253/254 (second floor)

In his lab in Department of Bioengineering at UCLA, Dr. Tawil’s research team has focused on understanding the mechanical characteristics of 3D fibrin constructs by using various approaches including diffusion, cross linking, etc.  Furthermore, they have examined cell behavior in 3D fibrin constructs including cell proliferation, differentiation, and migration. The team has examined various cell types including Mesenchymal stem cells, fibroblasts, keratinocytes and osteoblasts. Areas of research include:

3D Constructs to Study Bone Healing: The construct consists of fibrin, collagen, hydroxyapatite, and β-tricalcium phosphate (F-C-HA-TCP). The research team is now examining the Mesenchymal stem cells proliferation and their differentiation into osteoblasts in this construct.  They are also in the process of establishing a process to examine the controlled release of recombinant human bone morphogenetic proteins (rhBMP) from fibrin beads within the F-C-HA-TCP 3D constructs. The team is identifying the mechanism of action that guides mesenchymal stem cell proliferation and osteogenic differentiation within the 3D biomatrix by examining the expression of integrins and bone morphogenetic protein receptors. Finally, they will implant the 3D biomatrix into a rabbit femoral defect model and examine structural changes, rate of degradation, restoration, mineralization, ossification, and osseointegration.

In Vitro 3D Wound Healing Model: The research team has established in Vitro 3D wound healing model to study the intricate relationship between the various growth factors and cells that are known to play role in the wound healing process.  The 3D construct consists of 3 components: human dermal – derived fibroblasts incorporated in type I collagen representing the dermis, human dermal keratinocytes seeded on the top of fibroblasts/collagen 3D construct representing the epidermis, and finally a fibrin cylinder (or multiple cylinders) seeded in the middle of the construct representing the wound.  This fibrin cylinder contains one or more growth factors that might influence keratinocytes migration into or under the fibrin cylinder.  

Co – Delivering Fibroblasts and Keratinocytes in 3D Fibrin Constructs for the Treatment of Skin Wounds: The research team is testing the hypothesis that fibrin component concentration, as well as the spatial distribution and proportion of fibroblasts and keratinocytes, all affect cell behavior and signaling relevant to wound healing. These factors are ubiquitous in fibrin-based cell therapies for wound healing, yet have not been thoroughly studied.  This study furthers our understanding of cell-fibrin interactions, and enhances the therapeutic efficacy of fibrin-based cell carriers. To test our hypothesis, fibroblasts are homogeneously seeded in a novel in vitro 3D fibrin construct. Keratinocytes are encapsulated in fibrin beads and suspended in the main 3D fibrin construct to spatially control cell distribution.

Dr. Bill Tawil

Dr. Bill Tawil obtained his Bachelor degree in Biochemistry from the University of California at Berkeley. He then completed his Master and Doctorate degrees in Neuroscience at McGill University in Montreal studying the expression and function of adhesion cell surface receptors (integrins) in the Central Nervous System and during tumor metastasis. Subsequently, he spent four years of postdoctoral training at the Center for Cancer Research at MIT under the supervision of Dr. Richard Hynes investigating cell adhesion during the cell cycle. As a Scientist and a Senior Scientist at U.S. Surgical Corporation and at Baxter BioSurgery, he worked in the field of Tissue Regeneration examining products (synthetic and biologics) that successfully deliver bioactive substances and cells to enhance healing in soft and hard tissue defects. He, then, acted as a director of global expansion at Baxter BioSurgery responsible for scientific initiatives related to tissue engineering establishing collaborations between Baxter and other companies and academic institutions. He, then, hold a Director of R&D position at CR Bard.

Dr Tawil is presently a director in Program Management at Abbott Medical. Bill is also an adjunct professor in the Bioengineering Department at UCLA where he is continuing his research in Tissue Engineering, specifically on 3D constructs. He is on council for the Tissue Engineering and Regenerative Medicine (TERMIS) – North America society and on the Executive Editorial Board for the Tissue Engineering Journal. Bill was the co – Chair for TERMIS 2008 and 2016 meeting. He has been the treasurer for TERMIS since 2009. Bill served on the BOD for the Wound Healing Society (WHS) from 2000 to 2005 and he was the treasurer from 2002 to 2005. He was on the Program Committee for the WHS from 1998 – 2000 and again from 2005 – 2008 including the co – chair for the 2007 meeting. Bill believes strongly that the interaction between academia and industry is an expedient and successful way to get products to the patients.