Flow perfusion improves seeding of tissue engineering scaffolds withdifferent architectures
Alvarez-Barreto,JF; Linehan,SM; Shambaugh,RL; Sikavitsas,VI
Abstract Engineered bone grafts have been generated in static and dynamic systems byseeding and culturing osteoblastic cells on 3-D scaffolds. Seeding determines initial cellularityand cell spatial distribution throughout the scaffold, and affects cell-matrix interactions. Staticseeding often yields low seeding efficiencies and poor cell distributions; thus creating a need fortechniques that can improve these parameters. We have evaluated the effect of oscillating flowperfusion on seeding efficiency and spatial distribution of MC3T3-E1 pre-osteoblastic cells infibrous polystyrene matrices (20, 35 and 50-microm fibers) and foams prepared by salt leaching,using as controls statically seeded scaffolds. An additional control was investigated where staticseeding was followed by unidirectional perfusion. Oscillating perfusion resulted in the mostefficient technique by yielding higher seeding efficiencies, more homogeneous distribution andstronger cell-matrix interactions. Cell surface density increased withinoculation cell number andthen reached a maximum, but significant detachment occurred at greater flow rates. Oxygen plasmatreatment of the fibers greatly improved seeding efficiency. Having similar porosity and dimensions,fibrous matrices yielded higher cell surface densities than foams. Fluorescence microscopy andhistological analyses in polystyrene and PLLA scaffolds demonstrated that perfusion seeding producedmore homogeneous cell distribution, with fibrous matrices presenting greater uniformity than thefoams.
Keywords Biocompatible Materials; Perfusion
Annals of Biomedical Engineering
0090-6964, Volume 35, Issue 3, 2007, Pages 3-442
