Effects of Filtration Seeding on Cell Density, Spatial Distribution, and Proliferation in Nonwoven Fibrous Matrices

Abstract

The cell seeding density and spatial distribution in a 3-D scaffold are critical to the morphogenetic development of an engineered tissue. A dynamic depth-filtration seeding method was developed to improve the initial cell seeding density and spatial distribution in 3-D nonwoven fibrous matrices commonly used as tissue scaffolds. In this work, trophoblast-like ED27 cells were seeded in poly(ethylene terephthalate) (PET) matrices with various porosities (0.85-0.93). The effects of the initial concentration of cells in the suspension used to seed the PET matrix and the pore size of the matrix on the resulting seeding density and subsequent cell proliferation and tissue development were studied. Compared to the conventional static seeding method, the dynamic depth-filtration seeding method gave a significantly higher initial seeding density (2-4 x 10(7) vs 4 x 10(6) cells/cm3), more uniform cell distribution, and a higher final cell density in the tissue scaffold. The more uniform initial cell spatial distribution from the filtration seeding method also led to more cells in S phase and a prolonged proliferation period. However, both uniform spatial cell distribution and the pore size of the matrices are important to cell proliferation and morphological development in the seeded tissue scaffold. Large-pore matrices led to the formation of cell aggregates and thus might reduce cell proliferation. The dynamic depth-filtration seeding method is better in providing a higher initial seeding density and more uniform cell distribution and is easier to apply to large tissue scaffolds. A depth-filtration model was also developed and can be used to simulate the seeding process and to predict the maximum initial seeding densities in matrices with different porosities.

Effect of surface acoustic waves on the viability, proliferation and differentiation of primary osteoblast-like cells

“…The static method resulted in a statistically lower uniformity, consistent with the nonuniform spatial cell distributions reported by several groups. 4,6,21,22 This low uniformity may be explained by the difficulty in evenly distributing the small volume of cell suspension over the scaffold surface and by the intrinsically weak mechanism of infusion ͑i.e., via gravity and capillary action͒.…”

Human clinical experience with adipose precursor cells seeded on hyaluronic acid-based spongy scaffolds

“…Its architecture provides not only an instructive cue for the conversion and spatial orientation [25] of precursor cells into a functional tissue [26] but also properties at a macroscale level provide a number of tissue functions including osmosis, molecular and nutrient transport [12,27]. A central event in adipogenesis is the active remodelling of the ECM [28]. Biodegradable scaffolds designed to meet tissue engineering purposes mimic the in vivo three-dimensional extracellular microarchitecture to provide precursors the signals to develop in desirable phenotypes, the means for cell expansion and the space for the newly deposited ECM to achieve properties similar to those of the native tissue [1,29].…”

Biodegradable elastomeric scaffolds with basic fibroblast growth factor release

“…The scaffolds were sterilized by UV irradiation for 30 min in a laminar flow hood. Cells at a density of 2 x10 6 cells/mL were seeded into scaffolds using the filtration cell seeding method [28]. The seeded samples were then cultured in a 24-well polystyrene tissue culture plate with DMEM supplemented with 10% FBS as culture medium.…”