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New Publication: Tissue Engineered Vascular Grafts: Current State of the Field.

Expert Rev Med Devices. 2017 Apr 27. doi: 10.1080/17434440.2017.1324293. [Epub ahead of print]

Tissue Engineered Vascular Grafts: Current State of the Field.

Ong CS1, Zhou X1, Huang CY2, Fukunishi T1, Zhang H1, Hibino N1.

Author information

1. Division of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, Maryland, USA.
2. Department of Physics & Astronomy, Johns Hopkins University, Baltimore, Maryland, USA.

Abstract

INTRODUCTION:

Conventional synthetic vascular grafts are limited by the inability to remodel, as well as issues of patency at smaller diameters. Tissue-engineered vascular grafts (TEVGs), constructed from biologically active cells and biodegradable scaffolds have the potential to overcome these limitations, and provide growth capacity and self-repair.

Areas covered: This article outlines the TEVG design, biodegradable scaffolds, TEVG fabrication methods, cell seeding, drug delivery, strategies to reduce wait times, clinical trials, as well as a 5-year view with expert commentary.

Expert Commentary: TEVG technology has progressed significantly with advances in scaffold material and design, graft design, cell seeding and drug delivery. Strategies have been put in place to reduce wait times and improve “off-the-shelf” capability of TEVGs. More recently, clinical trials have been conducted to investigate the clinical applications of TEVGs.

KEYWORDS:

Biomaterial; Cell seeding; Tissue Engineered Vascular Grafts; Vascular Grafts; Vascular Surgery

DOI: 10.1080/17434440.2017.1324293

Figure 1 20170316

Accepted Publication: Creation of Cardiac Tissue Exhibiting Mechanical Integration of Spheroids Using 3D Bioprinting

New publication coming soon: https://www.jove.com/video/55438/creation-cardiac-tissue-exhibiting-mechanical-integration-spheroids

JoVE Capture.JPG

Accepted Publication: Role of Bone Marrow Mononuclear Cell Seeding for Nanofiber Vascular Grafts

Title: Role of Bone Marrow Mononuclear Cell Seeding for Nanofiber Vascular Grafts

Authors: Takuma Fukunishi, MD1 # , Cameron A. Best, BA2 # , Chin Siang Ong, MD1 , Tyler Groehl, PhD3 , James Reinhardt, PhD2 , Tai Yi, MD2 , Hideki Miyachi, MD, PhD2 , Huaitao Zhang, BS1 , Toshiharu Shinoka, MD, PhD2 , Christopher K. Breuer, MD2 , Jed Johnson, PhD3 , Narutoshi Hibino, MD, PhD1, *

Affiliations:

1 Department of Cardiac Surgery, John Hopkins University, Baltimore, MD
2 Tissue Engineering and Surgical Research, Nationwide Children’s Hospital, Columbus, OH
3 Nanofiber Solutions, Inc. Columbus, OH

# Equally contributing first authors

Journal: Tissue Engineering Part A

New Publication: Preclinical study of patient-specific cell-free nanofiber tissue-engineered vascular grafts using 3-dimensional printing in a sheep model.

J Thorac Cardiovasc Surg. 2017 Apr;153(4):924-932. doi: 10.1016/j.jtcvs.2016.10.066. Epub 2016 Nov 14.

Preclinical study of patient-specific cell-free nanofiber tissue-engineered vascular grafts using 3-dimensional printing in a sheep model.

Fukunishi T1, Best CA2, Sugiura T2, Opfermann J3, Ong CS1, Shinoka T2, Breuer CK2, Krieger A3, Johnson J4, Hibino N5.

Author information

1. Department of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, Md.
2. Tissue Engineering and Surgical Research, Nationwide Children’s Hospital, Columbus, Ohio.
3. The Sheikh Zayed Institute for Pediatric Surgical Innovation, Children’s National Medical Center, Washington, DC.
4. Nanofiber Solutions Inc, Columbus, Ohio.
5. Department of Cardiac Surgery, Johns Hopkins Hospital, Baltimore, Md. Electronic address: nhibino1@jhmi.edu.

Abstract

BACKGROUND:

Tissue-engineered vascular grafts (TEVGs) offer potential to overcome limitations of current approaches for reconstruction in congenital heart disease by providing biodegradable scaffolds on which autologous cells proliferate and provide physiologic functionality. However, current TEVGs do not address the diverse anatomic requirements of individual patients. This study explores the feasibility of creating patient-specific TEVGs by combining 3-dimensional (3D) printing and electrospinning technology.

METHODS:

An electrospinning mandrel was 3D-printed after computer-aided design based on preoperative imaging of the ovine thoracic inferior vena cava (IVC). TEVG scaffolds were then electrospun around the 3D-printed mandrel. Six patient-specific TEVGs were implanted as cell-free IVC interposition conduits in a sheep model and explanted after 6 months for histologic, biochemical, and biomechanical evaluation.

RESULTS:

All sheep survived without complications, and all grafts were patent without aneurysm formation or ectopic calcification. Serial angiography revealed significant decreases in TEVG pressure gradients between 3 and 6 months as the grafts remodeled. At explant, the nanofiber scaffold was nearly completely resorbed and the TEVG showed similar mechanical properties to that of native IVC. Histological analysis demonstrated an organized smooth muscle cell layer, extracellular matrix deposition, and endothelialization. No significant difference in elastin and collagen content between the TEVG and native IVC was identified. There was a significant positive correlation between wall thickness and CD68+macrophage infiltration into the TEVG.

CONCLUSIONS:

Creation of patient-specific nanofiber TEVGs by combining electrospinning and 3D printing is a feasible technology as future clinical option. Further preclinical studies involving more complex anatomical shapes are warranted.

Copyright © 2016. Published by Elsevier Inc.

KEYWORDS:

3D printing; Fontan circulation; cell-free tissue engineering; congenital heart disease; electrospun nanofibers; patient-specific; preclinical study; sheep model; tissue-engineered vascular graft

DOI: 10.1016/j.jtcvs.2016.10.066