Animal and in vitro models for the study of hair follicles

Since the way in which the hair follicle functions is not well understood, many hair disorders are poorly controlled. A range of in vitro and in vivo models have therefore been developed to investigate the cell biological and biochemical mechanisms involved in the organization of this complex tissue. These range from cultures of a single cell type, such as those of the regulatory, mesenchyme-derived dermal papilla, through organ culture of isolated follicles to natural or genetically manipulated animal models. Each system has advantages and disadvantages for studying particular aspects of follicular function and some are potentially useful for the development of novel treatments for hair disorders.