Functional Polymer Scaffolds for Blood Vessel Tissue Engineering

Bone is a highly vascularized tissue, and its development, maturation, remodeling, and regeneration are dependent on a tight regulation of blood vessel supply. This condition also has to be taken into consideration in the context of the development of artificial tissue substitutes. In classic tissue engineering, bone-forming cells such as primary osteoblasts or mesenchymal stem cells are introduced into suitable scaffolds and implanted in order to treat critical-size bone defects. However, such tissue substitutes are initially avascular. Because of the occurrence of hypoxic conditions, especially in larger tissue substitutes, this leads to the death of the implanted cells. Therefore, it is necessary to devise vascularization strategies aiming at fast and efficient vascularization of implanted artificial tissues. In this review article, we present and discuss the current vascularization strategies in bone tissue engineering. These are based on the use of angiogenic growth factors, the co-implantation of blood vessel forming cells, the ex vivo microfabrication of blood vessels by means of bioprinting, and surgical methods for creating surgically transferable composite tissues.

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Structure and Properties of Poly(α-hydroxyl acids)/Nano Hydroxyapatite Composite Scaffolds

MRS Proceedings ◽

10.1557/proc-735-c11.37 ◽

2002 ◽

Vol 735 ◽

Cited By ~ 1

Author(s):

Guobao Wei ◽

Peter X. Ma

Keyword(s):

Tissue Engineering ◽

Pore Structure ◽

The Body ◽

Polymer Scaffolds ◽

Composite Scaffolds ◽

Average Pore ◽

Thermally Induced ◽

Tissue Engineering Approach ◽

Biodegradable Poly ◽

Organ Failures

ABSTRACTTissue losses and organ failures resulting from injuries or diseases remain frequent and serious health problems despite great advances in medical technologies. Transplantation and reconstructive surgeries are seriously challenged by donor tissue shortage. We take a tissue engineering approach to design 3D scaffolds for cells to grow and synthesize new tissues. The scaffolds are biodegradable and will be absorbed after fulfilling the purpose as 3D templates, leaving nothing foreign in the body. To better mimic natural bone structurally, mechanically and biologically, nano-sized hydroxyapatite particles (N-HAP) were formulated with biodegradable poly(α-hydroxyl acids) to form composite scaffolds with well-controlled pore structures using thermally induced phase separation (TIPS) in this work. The pore structure and mechanical properties of the scaffolds were optimized by the use of multiple solvent systems, different quenching rates and quenching depths. The fabricated scaffolds possessed porosities higher than 90% and average pore sizes ranging from 50 to 500 μm. The scaffolds containing N-HAP maintained open and regular 3D pore structure similar to those of plain polymer scaffolds, implying that N-HAP particles were dispersed within the polymer pore walls of the scaffolds. The addition of N-HAP increased the compressive modulus by 20∼80% over that of plain polymer scaffolds. These results indicate that poly(α-hydroxyl acids)/N-HAP scaffolds may provide excellent 3D substrates for bone tissue engineering.

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Spatiotemporal blood vessel specification at the osteogenesis and angiogenesis interface of biomimetic nanofiber-enabled bone tissue engineering

Biomaterials ◽

10.1016/j.biomaterials.2021.121041 ◽

2021 ◽

pp. 121041

Author(s):

Yuankun Zhai ◽

Kevin Schilling ◽

Tao Wang ◽

Mirna El Khatib ◽

Sergei Vinogradov ◽

...

Keyword(s):

Tissue Engineering ◽

Blood Vessel ◽

Bone Tissue Engineering ◽

Bone Tissue

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Polymer Scaffolds for Anterior Cruciate Ligament Tissue Engineering

Polymers and Polymeric Composites: A Reference Series - Cellulose-Based Superabsorbent Hydrogels ◽

10.1007/978-3-319-92066-5_14-1 ◽

2018 ◽

pp. 1-30

Author(s):

Fiona Serack ◽

Nathaniel Holwell ◽

Brian G. Amsden

Keyword(s):

Tissue Engineering ◽

Anterior Cruciate Ligament ◽

Cruciate Ligament ◽

Polymer Scaffolds ◽

Anterior Cruciate ◽

Ligament Tissue Engineering

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Production of fibrous polymer scaffolds for tissue engineering using an automated solution blow spinning system

Research on Biomedical Engineering ◽

10.1590/2446-4740.180039 ◽

2018 ◽

Vol 34 (3) ◽

pp. 273-278 ◽

Cited By ~ 1

Author(s):

Alessandra Forgatti Hell ◽

Márcia Mayumi Omi Simbara ◽

Paulo Rodrigues ◽

Danilo Akio Kakazu ◽

Sônia Maria Malmonge

Keyword(s):

Tissue Engineering ◽

Polymer Scaffolds ◽

Fibrous Polymer ◽

Solution Blow Spinning

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Stereolithographic rendering of low molecular weight polymer scaffolds for bone tissue engineering

Innovative Developments in Design and Manufacturing ◽

10.1201/9780203859476-11 ◽

2009 ◽

pp. 55-62

Keyword(s):

Tissue Engineering ◽

Molecular Weight ◽

Bone Tissue Engineering ◽

Bone Tissue ◽

Low Molecular Weight ◽

Polymer Scaffolds ◽

Molecular Weight Polymer

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The Use of Polymer Scaffolds in Skeletal Tissue Engineering Applications

Journal of Craniofacial Surgery ◽

10.1097/scs.0b013e3181a9574b ◽

2009 ◽

Vol 20 (3) ◽

pp. 860-861 ◽

Cited By ~ 4

Author(s):

Deepak M. Gupta ◽

Nicholas J. Panetta ◽

Michael T. Longaker

Keyword(s):

Tissue Engineering ◽

Polymer Scaffolds ◽

Engineering Applications ◽

Skeletal Tissue

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Sustained VEGF delivery via PLGA nanoparticles promotes vascular growth

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00199.2009 ◽

2010 ◽

Vol 298 (6) ◽

pp. H1959-H1965 ◽

Cited By ~ 92

Author(s):

Justin S. Golub ◽

Young-tae Kim ◽

Craig L. Duvall ◽

Ravi V. Bellamkonda ◽

Divya Gupta ◽

...

Keyword(s):

Tissue Engineering ◽

Blood Vessel ◽

Femoral Artery ◽

Release Kinetics ◽

Aortic Ring ◽

Plga Nanoparticles ◽

Cardiovascular Medicine ◽

Vessel Growth ◽

Vessel Volume

Technologies to increase tissue vascularity are critically important to the fields of tissue engineering and cardiovascular medicine. Currently, limited technologies exist to encourage angiogenesis and arteriogenesis in a controlled manner. In the present study, we describe an injectable controlled release system consisting of VEGF encapsulated in poly(lactic- co-glycolic acid) (PLGA) nanoparticles (NPs). The majority of VEGF was released gradually over 2–4 days from the NPs as determined by an ELISA release kinetics experiment. An in vitro aortic ring bioassay was used to verify the bioactivity of VEGF-NPs compared with empty NPs and no treatment. A mouse femoral artery ischemia model was then used to measure revascularization in VEGF-NP-treated limbs compared with limbs treated with naked VEGF and saline. 129/Sv mice were anesthetized with isoflurane, and a region of the common femoral artery and vein was ligated and excised. Mice were then injected with VEGF-NPs, naked VEGF, or saline. After 4 days, three-dimensional microcomputed tomography angiography was used to quantify vessel growth and morphology. Mice that received VEGF-NP treatment showed a significant increase in total vessel volume and vessel connectivity compared with 5 μg VEGF, 2.5 μg VEGF, and saline treatment (all P < 0.001). When the yield of the fabrication process was taken into account, VEGF-NPs were over an order of magnitude more potent than naked VEGF in increasing blood vessel volume. Differences between the VEGF-NP group and all other groups were even greater when only small-sized vessels under 300 μm diameter were analyzed. In conclusion, sustained VEGF delivery via PLGA NPs shows promise for encouraging blood vessel growth in tissue engineering and cardiovascular medicine applications.

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