Osteogenesis by factor(s) isolated from mouse osteosarcoma cells in combination with collagen.

An osteogenic factor(s) was extracted with acetic acid from cultures of mouse osteosarcoma cells. The extract was mixed with acid-soluble human skin collagen as a carrier and the mixture was aggregated by dialysis against 0.02 M Na2HPO4. Thirty days after implanting the resulting precipitate into the muscle pouch of mice, new bone formation was observed at the site of implantation. Only fibrous tissue was formed in controls implanted with acid-soluble collagen alone. Therefore, it was concluded that the osteogenic factor(s) from the osteosarcoma cultures is an acid-soluble, non-dialyzable substance that interacts with collagen.