Processing cell-seeded polyester scaffolds for histology.
Biodegradable 3-dimensional scaffolds of various morphologies are currently being developed for tissue engineering. Poly(lactide-co-glycolide)s (PLGAs) of various lactide to glycolide ratios are frequently used for such applications. Tissue engineering involves an in vitro stage during which cells are seeded onto scaffolds and allowed to settle and/or grow for various time periods. To assess cell distribution and/or tissue formation throughout the scaffolds during this in vitro stage, techniques such as confocal microscopy and magnetic resonance imaging have been applied. However, such cultured scaffolds have been refractory to histological evaluation because of numerous technical difficulties. We describe a method to prepare histological sections of cell cultured PLGA scaffolds for tissue engineering. The technique involves in situ labeling of cultured scaffolds, infiltration of the scaffolds with a 10% poly(vinyl alcohol) solution under a low vacuum, and cryosectioning of samples onto acid-treated glass coverslips. Sections obtained with this technique show cell distribution and cell-tissue morphology on the pore wall structures of entire centimeter-thick scaffolds. This rapid and easy technique allows for fast evaluation of tissues grown on biodegradable scaffolds.