HiEpiXLTM Mammary Epithelial Cell Expansion Medium is designed for in vitro cultivation and expansion of human mammary epithelial cells (HMEC) under serum free conditions. It contains basal medium (Part A), mammary epithelial cell growth supplement (Part B) and bovine pituitary extract (Part C). HiEpiXLTM Mammary Epithelial Cell Expansion Medium is designed for in vitro cultivation and expansion of human mammary epithelial cells (HMEC) under serum free conditions. It contains basal medium (Part A), mammary epithelial cell growth supplement (Part B) and bovine pituitary extract (Part C). Part A consists of inorganic, organic salts, amino acids, vitamins and sodium bicarbonate. Part B consists of growth factors and nutrients necessary for growth of mammary epithelial cells. Part C is a bovine pituitary extract. This medium and supplement is devoid of antibiotics and antimycotics.