Contraction of Collagen Gels Seeded with Canine Endotenon Cells

Principal Investigator: Peter C. Amadio, M.D.
Project Coordinator: Yulong Sun, M.D. — sun.yulong@mayo.edu

Figure 1: Collagen concentrations. Left: 0.5 concentration, middle 1.0 concentrations, right 1.5 concentration.

Collagen is the most common protein in the human body and is the major component of the extracellular matrix that links all the connective tissue and provides the tensile strength in tissue. Collagen synthesis and remodeling are very important for wound healing, degenerative diseases, and other disorders. Collagen contraction in the in vitro model is a useful tool to better understand the cell behavior, and potentially provide tissue engineering possibility. However, factors influencing contraction rate have not been well studied. The purpose of this study was to test the parameters that regulate the contraction of type I collagen seeded with canine endotenon cells. The following parameters were studied; cell density, dish type, and collagen concentration.

Cell Culture Dish Effect: Canine endotenon cells were obtained from the third passage of flexor tendon cell culture. Bovine dermal collagen gel was pre made (1.0 mg/ml Collagen concentration) on to two different type of cell culture dish (bacteriologic and regular cell culture dish) with 1x106 cell population seeded. The results showed that the contraction rate of the BCD dish was significantly higher than the RCD.

Cell Density Effect: Four different cell densities (0, 0.25, 0.5, 1.0 x 106 cells/ml) were test on the bacteriologic cell culture dish with 1.0mg/ml collagen concentration. The results demonstrated that the contraction rate increased with increase of cell density.

Collagen Concentration Effect: Four different collagen concentrations (0.25, 0.5, 1.0, 2.0mg/ml) were tested on the bacteriologic cell culture dish with 1.0 M/ml cell density (Fig. 1). The results indicated that contraction rate of higher collagen concentration was significantly lower than lower collagen concentration.

Our conclusions were that regular cell culture plate and high collagen concentration were negatively correlated to the gel contraction rate. Additionally, the bacteriologic cell dish with smooth surface and a high cell density increased contraction of collagen gels seeded with endotenon cells.