091 A reliable method to select human hair follicle for organ culture.

Jun-Kyu Oh, So-Hyun Park, Kyu-Han Kim, Jin-Ho Chung, Kwang-Hyun Cho, Hee-Chul Eun. Department of dermatology, Seoul national university, Seoul, Korea.

Among several in vitro models for hair growth studies, organ culture of hair follicle has been the most popular mothod principally to investigate growth factors thought to be involved in hair growth control mechanisms and to test viability of hair follicle which have had various ischemic or traumatic injuries. In such experiments, changes in hair growth are commonly used as the measure of activity and viability. But Robinson et al showed that the behavior of murine vibrissa follicles in organ culture is determined by the point in the hair growth cycle at which they are taken. In case of human hair, there have been no reliable methods to select hair follicles on specific hair cycle stage, so it has been difficult to evaluate the result of a experiment using hair follicle organ culture method. In this study we investigate a new method which can be used in humans to select hair follicles for organ culture. In three volunteers, hairs in 2 × 0.5 cm area of occipital scalp was cut and bleached by a agent containing H2O2. After 2 weeks biopsy was done in the bleached area and all hair follicles were microdissected. The growth of each hair during 2 weeks was measured and anagen terminal hair follicles were further divided into 3 groups by hair growth rate. Hair follicle organ culture was done in 3 groups and length of hair was measured on alternate days. The growth rate of hairs were compared among 3 groups. In result the growth rate of hair during organ culture was related to the hair growth rate in vivo, and it showed significant difference among 3 groups. Using this method, the result of a experiment using follicle organ culture method would be more reliable, and in conventional follicle organ culture the sufficient number of hair follicles are required to minimize this inherent error.