Fluorescence-activated cell sorting of PCK-26 antigen-positive cells enables selection of ovine esophageal epithelial cells with improved viability on scaffolds for esophagus tissue engineering.

Objective: For esophagus tissue engineering, isolation and proliferation of esophageal epithelial cells (EEC) is a pre-requisite for scaffold seeding to create constructs. The aim of this study was to sort EEC expressing cytokeratin markers and their proliferative subpopulations; also, to investigate the viability of differentiated EEC subpopulations on collagen scaffolds.
Methods: Ovine esophageal epithelial cells (OEECs) from sheep esophagus were analyzed using flow cytometry for pan cytokeratin (PCK-26) and proliferation cell nuclear antigen (PCNA). Using fluorescent-activated cell sorting, OEEC were separated and analyzed for PCNA expression. The OEEC subpopulations were seeded on collagen scaffolds for a week in vitro culture.
Results: Proliferation cell nuclear antigen was expressed in >45% of OEEC isolated. In flow cytometry, 30% OEEC were PCK-26 positive which exhibited a high-proliferative capacity of 80%. PCK-26-negative OECC exhibited a low-proliferative capability of 13%. Scanning electron microscopy demonstrated organized attachment and uniform scaffold coverage in PCK-26-positive cells.
Conclusion: Ovine esophageal epithelial cells can be divided into PCK-26-positive and negative subpopulations. PCK-26-positive OEEC constitute one-third of the isolated cells with high-proliferative capability. Seeding of PCK-26-positive OEEC on collagen scaffolds leads to uniform distribution of cells in vitro. In esophagus, tissue engineering PCK-26-positive OEEC subpopulation is important for optimal construct generation.