Cell culture of embryonic chick duodenal cells: preparation of epithelial-fibroblast bilayers and homotypic cultures of fibroblasts and epithelial cells.

A method for the primary cell culture of trypsin-dissociated embryonic chick duodenum is described. Both heterotypic (epithelial cells and fibroblasts together) and homotypic (highly enriched cultures of epithelial cells or fibroblasts alone) cell cultures were established. Dispersed duodenal epithelial cells and fibroblasts grown in 10% fetal bovine serum (FBS) spontaneously aggregated and proliferated as a bilayer of cells with the epithelial cells growing on top of the fibroblasts. Changing the serum supplement to 6% chicken serum (CS) and 4% FBS when the fibroblast monolayer reached confluence resulted in epithelial cell proliferation. Homotypic cultures of epithelial cells and fibroblasts were prepared and analyzed by scanning electron microscopy and transmission electron microscopy. Fibroblasts, isolated by differential adhesion and grown in 10% FBS, did not demonstrate measurable alkaline phosphatase activity. Homotypic epithelial cell cultures, isolated by floating them off the fibroblasts with collagenase, and maintained on collagen in 6% CS/4% FBS, demonstrated higher alkaline phosphatase-specific activity (16.1 +/- 2.3 U/mg protein) compared with epithelial-fibroblast bilayer cell cultures (12.1 +/- 1.3 U/mg protein).