Isolation and identification of human fetal adrenal medullary cells in vitro

A rapid method for the partial separation of human fetal adrenal medullary cells is described. Enzymatically dissociated human fetal adrenal cells were centrifuged on a preformed gradient of colloidal Silica particles (Percoll) in isotonic Earle's balanced salt buffer. This procedure leads to the formation of five fractions containing nonviable cells and debris, predominantly fetal zone cells, predominantly definitive zone cells and clumps of medullary cells, isolated medullary cells, and red blood cells. The medullary cells were then pooled and plated on plastic culture dishes coated with an extracellular matrix produced by cultured bovine corneal endothelial cells. Medullary cells plated on extracellular matrix demonstrated extensive neurite formation, facilitating their identification. Further identification of the cells as medullary in origin was confirmed using a specific catecholamine fluorescence technique.