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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

Histological examination of the vascular graft in a short axis cross-section (Pre-implantation).Hematoxylin and eosin staining reveals the internal and external margins are smooth and the pinhole by the pinholder are completely closed (A). Masson’s trichrome staining reveals the extensive collagenous ECM as blue (B). vWF (C) and CD31-positive vascular endothelial cells (D) are distributed to all parts of the graft.
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pone.0136681.g005: Histological examination of the vascular graft in a short axis cross-section (Pre-implantation).Hematoxylin and eosin staining reveals the internal and external margins are smooth and the pinhole by the pinholder are completely closed (A). Masson’s trichrome staining reveals the extensive collagenous ECM as blue (B). vWF (C) and CD31-positive vascular endothelial cells (D) are distributed to all parts of the graft.

Mentions: Although piercing of the spheroid resulted in making a hole immediately after the removal from the needle array, the pre-implantation vascular graft of the short axis cross-section showed complete closure of these holes (Fig 5). Masson’s trichrome staining revealed the extensive collagenous ECM as blue (Fig 5B). vWF and CD31-positive vascular endothelial cells were distributed to all parts of the tubular tissue (Fig 5C and 5D). After implantation, vWF, CD31 and CellTracker Red-positive endothelial cells were recognized at the inner side of the vessel. Furthermore, the vascular endothelial cells covered the inner surface of the vessel more continuously on the fifth day than on the second day (Fig 6). The number of endothelial cells in the tubular tissue, as well as in native rate aortae, was counted (Fig 7A). Significant increases in the number of endothelial cells were observed after implantation compared to the pre-implant tissue (Fig 7B).


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)

Histological examination of the vascular graft in a short axis cross-section (Pre-implantation).Hematoxylin and eosin staining reveals the internal and external margins are smooth and the pinhole by the pinholder are completely closed (A). Masson’s trichrome staining reveals the extensive collagenous ECM as blue (B). vWF (C) and CD31-positive vascular endothelial cells (D) are distributed to all parts of the graft.
© Copyright Policy
Related In: Results  -  Collection

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

pone.0136681.g005: Histological examination of the vascular graft in a short axis cross-section (Pre-implantation).Hematoxylin and eosin staining reveals the internal and external margins are smooth and the pinhole by the pinholder are completely closed (A). Masson’s trichrome staining reveals the extensive collagenous ECM as blue (B). vWF (C) and CD31-positive vascular endothelial cells (D) are distributed to all parts of the graft.
Mentions: Although piercing of the spheroid resulted in making a hole immediately after the removal from the needle array, the pre-implantation vascular graft of the short axis cross-section showed complete closure of these holes (Fig 5). Masson’s trichrome staining revealed the extensive collagenous ECM as blue (Fig 5B). vWF and CD31-positive vascular endothelial cells were distributed to all parts of the tubular tissue (Fig 5C and 5D). After implantation, vWF, CD31 and CellTracker Red-positive endothelial cells were recognized at the inner side of the vessel. Furthermore, the vascular endothelial cells covered the inner surface of the vessel more continuously on the fifth day than on the second day (Fig 6). The number of endothelial cells in the tubular tissue, as well as in native rate aortae, was counted (Fig 7A). Significant increases in the number of endothelial cells were observed after implantation compared to the pre-implant tissue (Fig 7B).

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