NSF EpSCoR The South Carolina Project for Organ Fabrication

EARB MEETING 2012

Biofabrication by BioPrintingAdvantages

• Precision in positioning cell types• Scaffold “free” (What are hydrogels?)

• “Mimics” Development (vs. expts in evolution)

• Potential for “scale up automation”• Solves the vascularization problem of thick

tissue constructs

Biofabrication by BioPrintingDisadvantages

• Explosion of interest but unsolved technology• Few pioneers 2005+

– Boland, Nakamura, Forgacs and their respective groups

Huvec cells survive printer and can be positioned 2D 3D tube printed in 2007 -- 1mm 2007 double layered (Huvec, aortic sm. Muscle) 1mm 2009 10 mm solid structures were printed but collapsed

Technology of great potential looking for new ideas and solutions

NSF RII Thrusts • Thrust Leaders are tactical leaders who lead teams

• Five Thrusts not Five Silos

• Shared Vision: build vascular constructs 2011-2012 milestone: 4mm X 27mm tubular prototype

having 6,000 subunits of living tissue

• All participate in the three steps of biofabrication pre-processingprocessingpostprocessing

TACTICAL APPROACHESThrust I – Modeling and Computer-Aided-Design

Mathematical Modeling, Software Design, ProgrammingLeader: Qi WangMembers: Brian Canada, Thomas Trusk, William Mondy, Xiaofeng Yang, Xinfeng Liu, Feng Gu, Xigiang Zheng

Thrust II – BioInk, Approaches to the Building Blocks Aggregates, Stem Cells, Hydrogels, Differentiation, Endothelialization

Leaders: Chris Drake and Richard ViscontiMembers: C. Bi, Agnes Nagy, Xuejun Wen

Thrust III – Biomechanical Testing Natural Vessels, Collagen Tubes, BioPrinted Tubes

Leader: Michael Sutton Members: Sue Lessner, Jay Potts, Mike Yost, Tarik Shazly, Esmail Jabbari

Thrust IV – Processing / Printing / Assembly Manual templates, Izumi-ink jet printing, Laser-printing, Magnetic Assembly,

MicrofluidicsLeader: Xuejun Wen Members: William Mondy, Frank Alexis, Scott Argraves, Yong Huang, Waleed Twal

Thrust V – Maturation ECM Synthesis, Perfusion, Bioreactors, Scaffolds, Small Molecules

Leader: Scott Argraves Members: Chris Drake, Waleed Twal, Xuejun Wen, Gear Grantees

NSF RII Thrusts • Thrust Leaders are tactical leaders who lead teams

• Five Thrusts not Five Silos

• Shared Vision: build vascular constructs 2011-2012 milestone: 4mm X 27mm tubular

prototype having 6,000 subunits of living tissue

Major Milestone for Year 3 – bioprint 4.5mm x 27 mm tubular construct

NSF RII Thrusts • Thrust Leaders are tactical leaders who lead teams

• Five Thrusts not Five Silos

• Shared Vision: build vascular constructs

• All participate in the three steps of biofabrication pre-processingprocessingpost-processing

Modeling Natural Properties

Thrusts I, III

Spheroid-Based VesselDesign Parameters

Computer Aided DesignVirtual Blueprints

Thrust I, IV

Spheroid Preparation Thrusts II, IV, V

Bioprinter/DispensorThrust IV team

Hydrogels/biomaterialsThrusts II, IV, V

Directed Differentiation Thrusts II, V

PerfusionEndothelialization

TestingThrusts , II, III, IV, V

MaturogensThrusts II, III, V

I. Pre-processing

II. Processing

III. Post-processing

All Thrusts Participate in Multiple Steps

of Bioprinting

Goals (Milestones) for Year 3

• Develop by mathematical modeling numerical predictive tools for the formation of vascular constructs by the deposition of multicellular aggregates/spheroids in a designer fashion.

– Spearheaded by Qi Wang/Thrust I leader

THRUST 1 PRESENTATIONLeader: Qi Wang

TACTICAL LEADER ------------------- QI Wang

Members: Brian Canada, Thomas Trusk, William Mondy, Xiaofeng Yang, Xinfeng Liu, Feng Gu and Xigiang Zheng

Goals (Milestones) for Year 3

•Prepare various types of cell spheroids +/- hydrogels (“BioInk”)Thrust I: Modeling of hydrogels that bind the cellular spheroids and enrich maturogensThrust II : stem cells, ECM, hydrogels (X.Bi, Chas So Univ)

Thrust IV: enhance production (microfluidics, laser assisted ) Thrust V: gelatin microcarrier spheroids: test bed for

maturogens etc.

•Build Inkjet type bioprinter to dispense living spheroids*

Goals (Milestones) Yr 3• Design and Build an inkjet printer

Designed by Xuejun Wen; assembled by Izumi Inc. 2 years in the making

Bill Mondy with Jorge V. L. Silva, Chief of the Division of Three Dimensional Technology, Renato Archer Center for Information Technology, Campinas Brazil.

β-testing

Beta testing (related to Thrust IV)

Early result of printed feature resolution demonstrated by the surface penetration of cardboard on the right and clay on the left. The pliability of clay allowed for smaller feature representation.

An eleven by ten array of physical impressions, with radii of 36 microns, created in a clay surface by bioprinter’s dispenser.

A. Series of 1 mm spheres printed during initial testing. B demonstrates 10 rows of 10 silicone spheres 1 mm in diameter printed in a z stack. C shows initial testing of bioprinter’s resolvable feature size.

A B C

Goals (Milestones) for Year 3

• Translate CAD into coordinates for the cellularized building blocks (spheroids) that can be used by the bioprinter to position (drop) the spheroids at specified locations– Thrust 1 Team Effort - Bill Mondy

Goals (Milestones) for Year 3• Dispense and assemble (“print”) living spheroids into variable-

sized tubular constructs (6 to 6000)

INK JET Izumi (Wen, Mondy, Dr. Waleed Twal)

Yong Huang (“drop on demand”) ** OTHER TISSUE ASSEMBLY APPROACHES

magnetic particles (Frank Alexis, Xuejun Wen)

laser assisted (Yong Huang) ** machined assisted devices/Argraves,Drake,Wen)

microfluidics – Xuejun Wen presentation

4 mm x 17mm

Yong HuangDepartment of Mechanical

Engineering

Clemson University, Clemson, SC

Scaffold-free Alginate Tube Fabrication using Inkjet and Laser printing

Presentation

Goals (Milestones) for Year 3

• Dispense and assemble (“print”) living spheroids into variable-sized tubular constructs (6-10 to 6000 model)

Izumi (Wen, Mondy et al.)

Yong Huang (“drop on demand”) **

Other experimental approaches

magnetic particles (Frank Alexis) laser assisted (Yong Huang) ** machined assisted devices

Goals (Milestones) for Year 3

• Dispense and assemble (“print”) living spheroids into variable-sized tubular constructs (6-10 to 6000 model)

Izumi (Wen, Mondy et al.) Yong Huang (“drop on demand”)

Other experimental approachesmagnetic particles (Frank Alexis, Xuejun Wen)laser assisted (Yong Huang)

machined assisted devices/Argraves,Wen)

Flow-through Bioreactor Template for 27mm x 4mm tubeThis template is designed to allow spheroids to fill a 4mm diameter tube-shaped space, which will allow the flow of media while the spheroids mature enough to be removed from the chamber.

Using a machined construct to arrange “carrier” spheroids into multi-layer tubes (test bed)

Goals (Milestones) for Year 3

• Dispense and assemble (“print”) living spheroids into variable-sized tubular constructs (6-10 to 6000 model)

Ink Jet Izumi (Wen, Mondy et al.) Yong Huang (“drop on demand”)

Other experimental approachesmagnetic particles (Frank Alexis, Xuejun Wen)laser assisted (Yong Huang)

machined assisted devices/Argraves,Wen)

Microfluidics: Xuejun Wen (Thrust IV leader)

Presentation by Xuejun Wen

THRUST IV: Microfluidic approach (Spheroid maker* + Spheroid printer)*

Goals (Milestones) for Year 3• Model and test for viability* and stability of “printed”

spheroids/constructs ( all thrusts) *grant opportunities

• Initiate post-processing differentiation and ways to

“endothelialize” tubular constructs (thrust II, V) • Develop post-processing mechanisms for accelerating

stabilization and maturation (focus on ECM) (thrust II, III V)

• Biomechanical testing: cf.natural (authentic) blood vessels to engineered constructs (bioprinted, extruded collagen tubes, etc. (thrust III)

Presentations (sequentially)+

• Thrust II - Chris Drake/Rick Visconti

• Thrust V - Scott Argraves

• Thrust III - Mike Sutton/Jay Potts

Preliminary analysis demonstrates that:• the measured in vivo longitudinal strain differed between the

main renal artery and the first branch by a factor of 2 (25% for main renal artery, 12% for first branch)

• the measured in-vivo circumferential strain differed between the main renal artery and the first branch by a factor of 2 (12% for main renal artery, 25% for first branch).”

Mondy-CAD “Blueprint”

Next level - 2013

Goals to reach the next level• Higher resolution CADs• Translation of CADs into programming for

directing printheads (dispensors)• Modeling & testing the biology of spheroid

formation and fusion• Hydrogel or ECM properties of Spheroids• Integration of printing (assembly) approaches• Endothelialization, Differentiation,Maturogens