Biography
Biography: Maryham S. Ibrahim
Abstract
Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis. The precise cause behind melanocyte destruction remains unknown. The epidermal melanocytes form a functional and structural unit with neighboring keratinocytes. The keratinocytes produce certain growth factors required for melanocyte growth and damage to keratinocytes may result in passive melanocyte death with the development of vitiligo. We performed this study to confirm the role of apoptosis in the pathogenesis of vitiligo through studying the expression of caspases-8, 9 & 3 and to determine the relation between the disease activity and the expression of these apoptotic markers. 20 skin biopsies were obtained from the edge of vitiligo lesion. Immunohistochemical staining for caspases-8, 9 & 3 was carried out. We demonstrated the expression of these apoptotic markers within both the epidermis and the dermal lymphocytes. We found that the expression of caspases-8, 9 & 3 was higher in depigmented epidermis when compared to normally pigmented epidermis either from vitiligo patients or from the normal control. The majority of apoptotic keratinocytes was found in the basal and suprabasal layers of epidermis. Regarding disease activity, the expression of these apoptotic markers was significantly higher in cases with active disease when compared to those with stable disease. Also, these apoptotic markers were expressed in the dermal lymphocytes. In conclusion vitiligo is not a disease limited to melanocyte death. Apoptosis of keratinocytes also clearly occurs and may play an important role in the development of the disease.