Chemically-defined medium for growth and differentiation of mixed epithelial and connective tissues in organ culture.

The effect on tissue differentiation and growth in vitro of certain of the factors implicated in collagen synthesis (ascorbic acid, alpha-ketoglutarate and oxygen) and the influence of hydrocortisone was studied using organ cultures of fetal mouse mandible as a mixed epithelial and connective tissue system. Using serum-free Waymouth's MB 752/1 chemically-defined medium, addition of high levels of ascorbic acid (300mug per ml), hydrocortisone (1mug per ml) and oxygen (95%) enhanced differentiation in a number of tissues, in particular skin and appendages, tooth germs and bone, while osteoid and dentine production were noticeable promoted. It is suggested that an essential aspect of media design for organ culture involves the incorporaation of collagen-promoting factors to the in vitro enviornment particularly with regard to the controlling role implicated for collagen in a variety of biological processess.