In situ tissue engineering for tracheal reconstruction using a luminar remodeling type of artificial trachea.
BACKGROUND
After successful trials of tracheal reconstruction using mesh-type prostheses in canine models, the technique has been applied clinically to human patients since 2002. To enhance tissue regeneration, we have applied a new tissue engineering approach to this mesh-type prosthesis.


METHODS
The prosthesis consists of a polypropylene mesh tube reinforced with a polypropylene spiral and atelocollagen layer. The cervical tracheas of 18 beagle dogs were replaced with the prosthesis. The collagen layer was soaked with peripheral blood in 6 of the dogs, with bone marrow aspirate in another 6, and with autologous multipotential bone marrow-derived cells (mesenchymal stem cells) in another 6. The dogs were humanely killed at 1 to 12 months after the operation.


RESULTS
All 18 dogs survived the postoperative period. Bronchoscopically, 3 of 4 dogs in the peripheral blood group showed stenosis, whereas no stenosis was evident in all 8 of the dogs in the bone marrow and mesenchymal stem cell groups 6 months after the operation. Faster epithelialization and fewer complications, such as mesh exposure and luminal stenosis, were observed in these two groups than in the peripheral blood group. Histologically, the cells from autologous bone marrow were found to proliferate into the tracheal tissue during the first month. Cilial movement in these two groups was faster than that in the peripheral blood group and recovered to 80% to 90% of the normal level.


CONCLUSIONS
Bone marrow aspirate and mesenchymal stem cells enhance the regeneration of the tracheal mucosa on this prosthesis. This in situ tissue engineering approach may facilitate tracheal reconstruction in the clinical setting.
Nakamura
Tatsuo
T
Department of Bioartificial Organs, Institute for Frontier Medical Sciences, Kyoto University, Kyoto, Japan. nakamura@frontier.kyoto-u.ac.jp
Sato
Toshihiko
T
Araki
Masato
M
Ichihara
Satoshi
S
Nakada
Akira
A
Yoshitani
Makoto
M
Itoi
Shin-ichi
S
Yamashita
Masaru
M
Kanemaru
Shin-ichi
S
Omori
Kouichi
K
Hori
Yoshio
Y
Endo
Katsuaki
K
Inada
Yuji
Y
Hayakawa
Katsumi
K
D000818:Animals; D001854:Bone Marrow Cells / Q000502:physiology; D001999:Bronchoscopy; D049109:Cell Proliferation; D002923:Cilia / Q000473:pathology / Q000502:physiology; D003094:Collagen; D004285:Dogs; D008279:Magnetic Resonance Imaging; D008648:Mesoderm / Q000166:cytology / Q000502:physiology; D039902:Multipotent Stem Cells; D011126:Polypropylenes; D019736:Prostheses and Implants; D013526:Surgical Mesh; D023822:Tissue Engineering / Q000379:methods*; D054457:Tissue Scaffolds; D014132:Trachea / Q000473:pathology / Q000601:surgery
D011126:Polypropylenes; D003094:Collagen