Skin Stem Cells; Definition, Function, Importance and Methods of Isolation

Abstract

Stem cells (SCs) are a population of undifferentiated cells with high self-renewing and differentiation potency. On the basis of origin, SCs are divided into four main groups: embryonic stem cells (ESCs), fetal stem cells (FSCs), induced pluripotent stem cells (iPSCs), and adult stem cells (ASCs). Interestingly, in different literatures, ASCs are considered as unipotent progenitor cells, multipotent stem cells or even pluripotent stem cells with variety of differentiation potential. ASCs reside in many adult tissues such as liver, bone marrow, adipose tissue, neural tissues, skin and etc. Among adult tissues, skin is considered as a fast self-renewing tissue which is capable to reconstruct itself during skin homeostasis and injuries. In fact, skin is mentioned as a pool of different types of SCs including keratinocyte stem cells (KSCs), hair follicle stem cells (HFSCs) and sebaceous gland stem cells (SGSCs). During skin regeneration, cooperation between these stem cells is essential for reconstruction of skin. Among these SCs, KSCs are most common cells in epidermis layer (mostly in basal layer) which are the important population of SCs for regeneration of epidermis. Herein, we reviewed different methods for skin stem cells isolation and characterization, and their potential for clinical application.