Exogenous transforming growth factor beta 1 alone does not improve early healing of medial collateral ligament in rabbits.
OBJECTIVE
To determine whether transforming growth factor beta 1 (TGF-beta1) improves early ligament healing.


METHODS
Experimental, controlled study of medial collateral ligaments (MCLs) in rabbits' knees.


METHODS
Research laboratory.


METHODS
Sixteen skeletally mature, New Zealand White female rabbits.


METHODS
Ten rabbits had a standardized gap injury made in the MCL of both knees. Three weeks later, a second operation was performed to inject 7 microg of TGF-beta1 in a carrier solution into the right knee MCL, while the left knee MCL was injected with carrier alone. The rabbits were killed 3 weeks after the injection of TGF-beta1 (6 weeks after the original injury). Six of the rabbits (12 knees) had no operation on the MCL and served as external normal controls.


METHODS
Biomechanical measures of the femur-MCL-tibia complex. Histologic evaluation of MCL cell and matrix organization. Transmission electron microscopy measures of MCL fibril diameters.


RESULTS
There were no statistically significant differences in the biomechanical measures, fibril diameter distributions and histologic evaluation of the injured MCLs treated with TGF-beta1 or carrier alone. Both groups of injured MCLs were significantly different from normal MCLs.


CONCLUSIONS
The results indicate that the dosage and route of delivery of TGF-beta1 did not lead to overt improvement in the healing of the injured MCL. Whether different doses or delivery methods, alone or in combination with TGF-beta1, or other growth factors would lead to improvement remains to be determined.
Hildebrand
Kevin A
KA
McCaig Centre for Joint Injury and Arthritis Research, University of Calgary, Alta. hildebrk@ucalgary.ca
Hiraoka
Histada
H
Hart
David A
DA
Shrive
Nigel G
NG
Frank
Cyril B
CB
D000818:Animals; D001696:Biomechanical Phenomena; D002921:Cicatrix; D003094:Collagen / Q000187:drug effects*; D007270:Injections, Intra-Articular; D017888:Medial Collateral Ligament, Knee / Q000187:drug effects*; D023421:Models, Animal; D011817:Rabbits; D016212:Transforming Growth Factor beta / Q000008:administration & dosage / Q000494:pharmacology*; D053773:Transforming Growth Factor beta1; D014945:Wound Healing / Q000187:drug effects*
D016212:Transforming Growth Factor beta; D053773:Transforming Growth Factor beta1; D003094:Collagen