Spatial Distribution of Cells Within Void Volume of a Chitosan-collagen Scaffold
Abstract
In tissue engineering, cells must be uniformly distributed within 3D scaffolds in order to receive adequate nutrition and oxygen. The objective of this project is to test a novel method to seed cells within a three-dimensional porous chitosan-collagen scaffold to achieve a uniform cell distribution in the Z direction and XY plane. Cells mixed in a collagen solution are seeded to the top of the scaffold and centrifuged to distribute the cells throughout the void spaces of the scaffold. The scaffolds are placed in a CO 2 incubator at 37 °C to allow the collagen-cell solution to gel, thus trapping the cells throughout the scaffold. The cells trapped in a collagen gel are observed for viability, proliferation, and distribution. Fluorescent microscopy is used to view the distribution of CellTracker red and DAPI-labeled cells within the scaffolds. Cell viability and proliferation in the scaffolds are compared to a two-dimensional monolayer cell culture and to cells distributed within three-dimensional collagen gels. The mean major pore size of the optimum dry scaffold is approximately 130 μm with a thickness of 800 μm. Preliminary observations show that the cells attach to the scaffold and are viable. Cell seeding efficiency of a scaffold or collagen gel is increased when seeded within a collagen solution. Due to the viscous nature of the collagen solution, a majority of cells are retained on the top surface of the scaffold. An increase in centrifugation increases cell penetration; however, with a decrease in cell viability. A balance in the viscous nature of the collagen and the centrifugal force has led to a uniform distribution of cells throughout the scaffold. A collagen solution of 2 mg/ml results in the best cell distribution in the XY plane among the samples, but cell growth decreases. The optimum seeding method of those tested was with a collagen solution of 1 mg/ml and a centrifugal force of 840 x g (2200 rpm). This method provided a uniform distribution of cells in the Z direction.
Collections
- OSU Theses [15752]