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Growth of postembryonic skin epithelial cells on collagen gels.

A procedure to extract and to purify acid-soluble collagen from rabbit skin and a technique to prepare a semi-transparent collagen gel to support growth of postembryonic rabbit, mouse, and human skin epithelial cells are presented. When a suspension of trypsin-released epithelial cells is plated on a collagen gel, the reorganization and growth of cells takes place in 3 stages. In stage 1, the germinative cells attach to, and assume a polyhydral configuration on the surface of the gel. In Stage 2, the cells migrate actively over the surface of the gel and reassociate into a multicellular colony. In Stage 3, the cells both multiply horizontally and vertically to the surface of the gel. A quantitative method to study growth and metabolism of isolated epidermal cells and the factors which induce or repress epidermal growth in vitro are outlined.