Isotonic biaxial loading of fibroblast-populated collagen gels: a versatile, low-cost system for the study of mechanobiology.
We developed a simple, versatile system for applying a range of biaxial loads to cell-matrix constructs for the study of mechanobiology. The system consists of porous polyethylene bars that are polymerized into a square fibroblast-populated gel and loaded by freely hanging weights attached to sutures routed through a custom loading rig. The cost to manufacture each mold/loading rig pair was less than US dollars 250 and the expected life of the components is up to 10 years. Neonatal and adult cardiac fibroblasts contracted gels to a decreasing extent as external load was increased ( P=0.003) and achieved contraction forces of up to 1.4 mN per million cells. Strain distributions were reasonably homogeneous in the central region of the gel (25% of gel area), but clearly nonhomogeneous outside that central region. The primary advantages of this system are simplicity, low cost, biaxial loading, and the ability to test for a dose-response effect of mechanical load. The current disadvantages are the inability to apply cycling loading and the inhomogeneities introduced by the use of rigid loading bars.
Knezevic
V
V
Department of Biomedical Engineering, Columbia University, 1210 Amsterdam Ave, New York, NY 10027, USA.
Sim
A J
AJ
Borg
T K
TK
Holmes
J W
JW
D000818:Animals; D000831:Animals, Newborn; D016880:Anisotropy; D018929:Cell Culture Techniques / Q000191:economics / Q000295:instrumentation* / Q000379:methods; D002478:Cells, Cultured; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005347:Fibroblasts / Q000502:physiology*; D005782:Gels; D006321:Heart / Q000502:physiology; D008567:Membranes, Artificial; D010812:Physical Stimulation / Q000295:instrumentation* / Q000379:methods*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014481:United States; D016474:Weight-Bearing / Q000502:physiology*
D005782:Gels; D008567:Membranes, Artificial