Melanocyte spheroids are formed by repetitive long-term trypsinization

Background: Autologous melanocyte transplantation plays an important role in the treatment of vitiligo. Objective: Previous studies have indicated that, compared with melanocytes growing in monolayers, melanocyte spheroids have a better survival in growth factor- and serum-deprived conditions. Methods: Melanocyte spheroids were obtained from human epidermis by repetitive long-term trypsinization and maintained an aggregated morphology for a short period in certain conditions. Results: Melanocyte spheroids were capable of growing into normal dendritic melanocytes in monolayer when they were harvested and reinoculated in 24-well plates. Immunohistochemical analysis of the melanocyte spheroids revealed that they were positive for HMB45, a melanosome-specific marker. No melanomas occurred when melanocyte spheroids were transplanted into mice. Conclusion: Our study provides a promising approach for melanocyte transplantation to treat vitiligo.

Neutral red staining and trypsin treatment to study viability and culture yield of Dermatophytes.

Dermatophytosis is common fungal infection of human being. To diagnose dermatophytic infections microscopic examination should be followed by culture which is essential step. Many times fungus may fail to grow on culture even after direct microscopy is positive due to non-Viability of fungus and it has been revealed that trypsinization enhances the rate of isolation of fungus on culture. Therefore, the study was undertaken with an aim to look for the viability and yield of dermatophytes on neutral red staining and trypsinization respectively.

Non-cultured epidermal suspension in vitiligo: From laboratory to clinic.

Background: Medical treatments are ineffective in many patients and surgical methods have therefore been developed. Objective: A review of autologous non-cultured melanocyte grafting techniques is proposed to obtain a successful repigmentation of vitiligo macules. Methods: Initially in 1992, we had developed a simplified grafting method which was carried out in the following two steps: production of blisters on the depigmented lesions by freezing with liquid nitrogen and injection in each blister of a non-cultured suspension of epidermal cells. The cellular suspension was obtained from samples of skin of the hair scalp after trypsinization. This very simple technique could be used at the dermatologist's clinic. Since 1998 (Olsson MJ, Juhlin L), quite comparable but improved and more sophisticated techniques have been proposed for the surgical treatment of vitiligo. These techniques require a laboratory set up to perform the melanocyte transplantation. The donor zone was usually taken on the gluteal region. The time of trypsinization was reduced to 60 minutes at 37΀C and the centrifuged cellular suspension added with hyaluronic acid (Van Geel) was directly applied on a dermabraded or laser abraded vitiligo lesions. Results: Whatever the technique chosen, repigmentation was evident within 25 to 30 days. Coalescence of the pigmented areas was spontaneously observed or obtained after UVB radiation. It is obvious that the complete repigmentation occurred more rapidly with the recent techniques compared with the initial method, but the efficiency was quite similar. Conclusion: The use of non-cultured epidermal suspension appears to be an effective, safe, and simple method for treating patients with achromic areas lacking melanocytes.