Flexor tendon tissue engineering: temporal distribution of donor tenocytes versus recipient cells.
BACKGROUND
Tissue-engineered tendon material may address tendon shortages in mutilating hand injuries. Tenocytes from rabbit flexor tendon can be successfully seeded onto acellularized tendons that are used as tendon constructs. These constructs in vivo exhibit a population of tenocyte-like cells; however, it is not known to what extent these cells are of donor or recipient origin. Furthermore, the temporal distribution is also not known.


METHODS
Tenocytes from New Zealand male rabbits were cultured and seeded onto acellularized rabbit forepaw flexor tendons (n = 48). These tendon constructs were transplanted into female recipients. Tendons were examined after 3, 6, 12, and 30 weeks using fluorescent in situ hybridization to detect the Y chromosome in the male donor cells. One unseeded, acellularized allograft in each animal was used as a control.


RESULTS
The donor male tenocytes populate the epitenon and endotenon of the grafts at greater numbers than the recipient female tenocytes at 3 and 6 weeks. The donor and recipient tenocytes are present jointly in the grafts until 12 weeks. At 30 weeks, nearly all cells are recipient tenocyte-like cells.


CONCLUSIONS
Donor male cells survive in decreasing numbers over time until 30 weeks. The presence of cells in tissue-engineered tendon grafts has been shown in prior studies to add to the strength of the constructs in vitro. This study shows that recipient cells can migrate into and repopulate the tendon construct. Cell seeding onto tendon material may create stronger constructs that will allow the initiation of motion earlier.
Thorfinn
Johan
J
Stanford, Calif.; Linköping, Sweden; and Singapore From the Section of Plastic Surgery, Department of Veterans Affairs and Division of Plastic Surgery, Stanford University Medical Center; Department of Plastic Surgery, Hand Surgery and Burns, University Hospital; and Department of Hand and Reconstructive Microsurgery, National University Health System.
Saber
Sepideh
S
Angelidis
Ioannis K
IK
Ki
Sae H
SH
Zhang
Andrew Y
AY
Chong
Alphonsus K
AK
Pham
Hung M
HM
Lee
Gordon K
GK
Chang
James
J
D000818:Animals; D002470:Cell Survival; D017690:Cell Transplantation / Q000379:methods*; D002478:Cells, Cultured; D004195:Disease Models, Animal; D005260:Female; D006085:Graft Survival; D006230:Hand Injuries / Q000601:surgery; D006801:Humans; D007150:Immunohistochemistry; D020007:Implants, Experimental; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D011336:Probability; D011817:Rabbits; D011897:Random Allocation; D012016:Reference Values; D013708:Tendon Injuries / Q000601:surgery; D013710:Tendons / Q000166:cytology* / Q000637:transplantation*; D013718:Tensile Strength; D023822:Tissue Engineering / Q000379:methods*