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Development of an In Vitro Assay to Evaluate Contractile Function of Mesenchymal Cells that Underwent Epithelial-Mesenchymal Transition
Published on: June 10, 2016
Myofibroblast upregulators are elevated in joint capsules in posttraumatic contractures.
Kevin A Hildebrand1, Mei Zhang, David A Hart
1McCaig Centre for Joint Injury and Arthritis Research. University of Calgary, Calgary, Canada. hildebrk@ucalgary.ca
Clinical Orthopaedics and Related Research
|January 2, 2007
Summary
Specific growth factors like transforming growth factor-beta1 are elevated in post-traumatic elbow contractures. A rabbit knee model successfully mimicked these human conditions, showing decreased growth factor levels over time.
Area of Science:
- Orthopedics
- Molecular Biology
- Biochemistry
Background:
- Post-traumatic elbow contractures are characterized by joint capsule stiffening.
- Specific growth factors are implicated in fibrotic processes leading to contractures.
Purpose of the Study:
- To investigate the expression of key growth factors in human elbow contractures.
- To validate a rabbit knee model for studying joint contractures.
- To analyze the temporal changes in growth factor levels within the contracture model.
Main Methods:
- Reverse transcription polymerase chain reaction (RT-PCR) was used to quantify mRNA levels.
- Target genes included transforming growth factor-beta1 (TGF-β1), connective tissue growth factor (CTGF), ED-A fibronectin, and alpha-smooth muscle actin (α-SMA).
- Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) served as the housekeeping gene for normalization.
Main Results:
- Elevated mRNA levels of TGF-β1, CTGF, and α-SMA were observed in human elbow contractures.
- The rabbit knee model showed increased mRNA levels for TGF-β1, CTGF, ED-A fibronectin, and α-SMA.
- In the rabbit model, mRNA levels of TGF-β1, CTGF, and α-SMA decreased over time.
Conclusions:
- The rabbit knee model effectively replicates human post-traumatic elbow contractures.
- Elevated levels of myofibroblast regulators and fibrogenic growth factors correlate with increased collagen production in contractures.
- Findings support the role of specific growth factors in the pathogenesis of joint contractures.
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