Tension is required for fibripositor formation
Zoher Kapacee1, Susan H Richardson, Yinhui Lu
1Wellcome Trust Centre for Cell-Matrix Research, University of Manchester, Faculty of Life Sciences, Michael Smith Building, Oxford Road, Manchester M13 9PT, England, United Kingdom.
Matrix Biology : Journal of the International Society for Matrix Biology
|February 12, 2008
Summary
Embryonic tendon cells create aligned collagen bundles and tendon-like structures in a novel 3D culture. Tension is crucial for maintaining fibripositors and organized collagen fibrils in these developing tendon constructs.
Area of Science:
- Biomaterials Science
- Cell Biology
- Tissue Engineering
Background:
- Embryonic tendon cells (ETCs) possess actin-rich fibripositors.
- These fibripositors are associated with parallel collagen fibrils in the extracellular matrix.
Purpose of the Study:
- To develop a 3D cell culture system for studying fibripositor function.
- To investigate the role of fibripositors in tendon development and structure.
Main Methods:
- Utilized a fixed-length fibrin gel 3D culture system.
- Cultured embryonic tendon cells (ETCs) within the fibrin gel for approximately 6 days.
- Observed the formation of collagen fibrils and fibripositors using microscopy.
Main Results:
- ETCs replaced fibrin with aligned, narrow-diameter collagen fibrils, forming tendon-like constructs.
- Fibripositors formation coincided with the appearance of parallel collagen fibrils.
- Constructs exhibited a tendon-like crimp.
- Cutting constructs led to loss of tension, fibripositors, and collagen organization.
Conclusions:
- The developed 3D culture system successfully mimics key aspects of embryonic tendon development.
- Fibripositors are integral to the formation and organization of collagen fibrils in tendon constructs.
- Tension plays a critical role in maintaining fibripositor function and the structural integrity of developing tendons.
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