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Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae.

Itoh M, Nakayama K, Noguchi R, Kamohara K, Furukawa K, Uchihashi K, Toda S, Oyama J, Node K, Morita S - PLoS ONE (2015)

Bottom Line: All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed.A layer of endothelial cells was confirmed five days after implantation.Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

View Article: PubMed Central - PubMed

Affiliation: Department of Thoracic and Cardiovascular Surgery, Faculty of Medicine, Saga University, Saga, Japan.

ABSTRACT

Background: Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a "Bio-3D printer"-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features.

Methods and results: Using a "Bio-3D printer," we made scaffold-free tubular tissues (inner diameter of 1.5 mm) from a total of 500 MCSs (2.5× 104 cells per one MCS) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%), and normal human dermal fibroblasts (50%). The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5) and fifth (n = 5) day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed. A layer of endothelial cells was confirmed five days after implantation.

Conclusions: The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

No MeSH data available.


Related in: MedlinePlus

An intra-operative photograph of end-to-end anastomosis between the tubular structure and the abdominal aorta of the nude rat (A).Color Doppler (left) and pulse Doppler (right) flow imaging of percutaneous ultrasonography show patent vessels on the fifth day after implantation (B).
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pone.0136681.g003: An intra-operative photograph of end-to-end anastomosis between the tubular structure and the abdominal aorta of the nude rat (A).Color Doppler (left) and pulse Doppler (right) flow imaging of percutaneous ultrasonography show patent vessels on the fifth day after implantation (B).

Mentions: Fifteen male F344-rnu/rnu athymic nude rats (10-week-old, CLEA, Tokyo, Japan) were used for this experiment. We used nude rats because the cells were of human origin. Without the use of nude rats, the implantation of the vascular construct would evoke severe rejection due to the introduction of xenogeneic substances. The tubular tissue was implanted into the infrarenal abdominal aortas under anesthesia with 1.5% isoflurane (vol/vol air). The end-to-end anastomosis was performed with a 9–0 polypropylene continuous suture (Fig 3A). No anticoagulation or anti-platelet drugs were given. The flow in the graft was assessed by ultrasonography (Toshiba, Tokyo, Japan). An off-line measurement of the average flow velocity was performed from the photocopied velocity wave forms using the Image J software program (National Institutes of Health, USA). At the end of the experiment, laparotomy was performed and both ends of the tubular tissue were clamped and the tubular tissue was removed. The animals were euthanized using the overinhalation of isoflurane.


Scaffold-Free Tubular Tissues Created by a Bio-3D Printer Undergo Remodeling and Endothelialization when Implanted in Rat Aortae.

Itoh M, Nakayama K, Noguchi R, Kamohara K, Furukawa K, Uchihashi K, Toda S, Oyama J, Node K, Morita S - PLoS ONE (2015)

An intra-operative photograph of end-to-end anastomosis between the tubular structure and the abdominal aorta of the nude rat (A).Color Doppler (left) and pulse Doppler (right) flow imaging of percutaneous ultrasonography show patent vessels on the fifth day after implantation (B).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4556622&req=5

pone.0136681.g003: An intra-operative photograph of end-to-end anastomosis between the tubular structure and the abdominal aorta of the nude rat (A).Color Doppler (left) and pulse Doppler (right) flow imaging of percutaneous ultrasonography show patent vessels on the fifth day after implantation (B).
Mentions: Fifteen male F344-rnu/rnu athymic nude rats (10-week-old, CLEA, Tokyo, Japan) were used for this experiment. We used nude rats because the cells were of human origin. Without the use of nude rats, the implantation of the vascular construct would evoke severe rejection due to the introduction of xenogeneic substances. The tubular tissue was implanted into the infrarenal abdominal aortas under anesthesia with 1.5% isoflurane (vol/vol air). The end-to-end anastomosis was performed with a 9–0 polypropylene continuous suture (Fig 3A). No anticoagulation or anti-platelet drugs were given. The flow in the graft was assessed by ultrasonography (Toshiba, Tokyo, Japan). An off-line measurement of the average flow velocity was performed from the photocopied velocity wave forms using the Image J software program (National Institutes of Health, USA). At the end of the experiment, laparotomy was performed and both ends of the tubular tissue were clamped and the tubular tissue was removed. The animals were euthanized using the overinhalation of isoflurane.

Bottom Line: All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed.A layer of endothelial cells was confirmed five days after implantation.Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

View Article: PubMed Central - PubMed

Affiliation: Department of Thoracic and Cardiovascular Surgery, Faculty of Medicine, Saga University, Saga, Japan.

ABSTRACT

Background: Small caliber vascular prostheses are not clinically available because synthetic vascular prostheses lack endothelial cells which modulate platelet activation, leukocyte adhesion, thrombosis, and the regulation of vasomotor tone by the production of vasoactive substances. We developed a novel method to create scaffold-free tubular tissue from multicellular spheroids (MCS) using a "Bio-3D printer"-based system. This system enables the creation of pre-designed three-dimensional structures using a computer controlled robotics system. With this system, we created a tubular structure and studied its biological features.

Methods and results: Using a "Bio-3D printer," we made scaffold-free tubular tissues (inner diameter of 1.5 mm) from a total of 500 MCSs (2.5× 104 cells per one MCS) composed of human umbilical vein endothelial cells (40%), human aortic smooth muscle cells (10%), and normal human dermal fibroblasts (50%). The tubular tissues were cultured in a perfusion system and implanted into the abdominal aortas of F344 nude rats. We assessed the flow by ultrasonography and performed histological examinations on the second (n = 5) and fifth (n = 5) day after implantation. All grafts were patent and remodeling of the tubular tissues (enlargement of the lumen area and thinning of the wall) was observed. A layer of endothelial cells was confirmed five days after implantation.

Conclusions: The scaffold-free tubular tissues made of MCS using a Bio-3D printer underwent remodeling and endothelialization. Further studies are warranted to elucidate the underlying mechanism of endothelialization and its function, as well as the long-term results.

No MeSH data available.


Related in: MedlinePlus