“…Human normal keratinocytes were obtained from foreskins and expanded using a low Ca# + serum-free medium (KSFM medium, Life Technologies) supplemented with 0n5 ng\ml epidermal growth factor (Life Technologies), 25 µg\ml bovine pituitary extract (Life Technologies), 200 units\ml penicillin, 200 µg\ml streptomycin (Boehringer Mannheim) and 0n25 µg\ml fungizone (Bristol-Myers Squibb), according to the technique of Boyce and Ham [14]. After two passages, the cells were seeded into 6-well multi-well plates and grown in keratinocyte growth medium without hydrocortisone (KGM medium, Promocell).…”