Autologous mesenchymal stem cell-mediated repair of tendon.
Mesenchymal stem cells (MSCs) were isolated from bone marrow of 18 adult New Zealand White rabbits. These cells were culture expanded, suspended in type I collagen gel, and implanted into a surgically induced defect in the donor s right patellar tendon. A cell-free collagen gel was implanted into an identical control defect in the left patellar tendon. Repair tissues were evaluated biomechanically (n = 13) and histomorphometrically (n = 5) at 4 weeks after surgery. Compared to their matched controls, the MSC-mediated repair tissue demonstrated significant increases of 26% (p < 0.001), 18% (p < 0. 01), and 33% (p < 0.02) in maximum stress, modulus, and strain energy density, respectively. Qualitatively, there appeared to be minor improvements in the histological appearance of some of the MSC- mediated repairs, including increased number of tenocytes and larger and more mature-looking collagen fiber bundles. Morphometrically, however, there were no significant left-right differences in nuclear aspect ratio (shape) or nuclear alignment (orientation). Therefore, delivering a large number of mesenchymal stem cells to a wound site can significantly improve its biomechanical properties by only 4 weeks but produce no visible improvement in its microstructure.
Awad
H A
HA
Noyes-Giannestras Biomechanics Laboratories, Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH 45221-0070, USA.
Butler
D L
DL
Boivin
G P
GP
Smith
F N
FN
Malaviya
P
P
Huibregtse
B
B
Caplan
A I
AI
D000818:Animals; D001696:Biomechanical Phenomena; D001854:Bone Marrow Cells / Q000166:cytology; D018929:Cell Culture Techniques / Q000379:methods; D002455:Cell Division; D017690:Cell Transplantation; D002478:Cells, Cultured; D008648:Mesoderm / Q000166:cytology*; D010329:Patella / Q000293:injuries; D011817:Rabbits; D013234:Stem Cells / Q000166:cytology*; D013708:Tendon Injuries / Q000503:physiopathology / Q000628:therapy*; D014182:Transplantation, Autologous