Razi Journal of Medical Sciences

Skin has some physiologic roles which are performed actively. One of the most important functions of skin is to take part in body immune system. Skin Immune system (SIS) which has local and extra-local effects plays its role through skin associated lymphoid tissues (SALT). SIS provides nonspecific (NI) and specific immunity (SI). NI is effective through PH, fatty acids, antibacterial substances found in sweat, normal skin flora e.g S. epidermidis and Corinebacterium, turnover of skin epithelial cells (keratinocytes) , and so on . SI which is mediated by Band T lymphocytes is a self-limited immunity with memory and specificity and is important in protection of the body.