Submit Manuscript | http://medcraveonline.com Abbreviations: Escs, epithelial stem cells; Melscs, melano- cytes stem cells; Ncscs, neural crest stem cells; Ipscs, patient-speci- fc stem cells; Hfscs, hair follicle stem cells; ORS, outer root sheath; BMP, bone morphogenetic proteins; EDN3, endothelin 34 Introduction The epidermal melanocytes protect the skin from UV rays and their functional destruction causes pigmentation disorders. The mutations of melanocyte stem cells cause melanomas. The mechanism of melanocyte differentiation and defning characteristics of melanocyte stem cells in humans are still not fully known. The autologous cultured melanocytes may be useful in the treatment of vitiligo. 1,2 In contrast to the foreskin melanocytes, expansion of adult melanocytes is not easy. Transplanted pigment cells are known to have repaired the affected area of skin discoloration from vitiligo. Vitiligo affects about two million people in the US. Vitiligo occurs when the body considers melanocytes, cells which give color to the skin, as foreign. In vitiligo the body’s own immune system attacks those cells, hence it is an autoimmune disease. Hair follicle has three types of stem cells which are vital to hair development. These incorporate epithelial stem cells (ESCs), melanocytes stem cells (MelSCs) and neural crest stem cells (NCSCs) which are known as human fetal stem cells (hFSCs). 3 Modeling of neural crest induction, melanocyte specifcation, and disease-related pigmentation defects in hESCs and patient-specifc iPSCs has been reported. 4 The safety and tolerability of subretinal transplantation of human embryonic-stem-cell (hESCs)-derived retinal pigment epithelium in Asians for the treatment of macular degeneration has been reported. 5 It has been confrmed that Protease- activated receptor-2 is involved in melanogenesis by mediating stem cell factor production in keratinocytes. 6 The enthusiasm for vitiligo exploration is coordinated towards the repositories of stem cells, especially the hFSCs. We hereby summarize recent advances in studies of pluripotent stem cells and its utility in vitiligo with specifc accentuation on hFSCs. Reconstruction of pigmentary system using stem cell technology Melanin production gives the skin its characteristic pigmentation and increases during sun exposure to protect the cells from the DNA- damaging effects of UV light. Melanocytes have been generated from human embryonic stem cells. The approach involves growing the stem cells in a carefully controlled manner while subjecting them to the specifc chemical signals that drive the formation of melanocytes in a developing embryo. It has not been possible to generate melanocytes at different stages of development including mature, fully functional and immature precursors. How melanocytes develop ad function normally, and how failure in these processes lead to diseases, is a matter of study. The hair follicle is a constantly renewing, where 66% of the lower follicle (travel part) totally is recovered over the hair cycle, while the staying upper lasting segment is kept up. 7 The irregular hair cycle comprises three phases of hair follicle viz. development (anagen), trailed by a relapse stage (catagen), and a resting stage (telogen). Melanocytes show up at the onset of anagen stage where they effectively multiply and separate into developed melanocytes. Throughout catagen, the melanocytes are drained from the follicles by apoptosis. Melanocytes go missing in telogen hair follicle until melanogenesis starts in the ensuing anagen stage. Given this regenerative cycle of melanogenesis, the presence of the stem cells for follicular melanocytes has been recommended over 10years. 8 Pluripotent stem cell technology offers a promising approach for studying human melanocyte development and disease. Timed exposure to activators of WNT, Bone morphogenetic proteins (BMP), and Endothelin 3 (EDN3) signaling triggers the sequential induction of neural crest and melanocyte precursor fates under dual-SMAD- inhibition condition. 4 Using a SOX10::GFP human embryonic stem cell (hESC) reporter line, it was demonstrated that the temporal onset of WNT activation is critical for human neural crest induction. J Stem Cell Res Ther. 2017;2(5):162‒164. 162 © 2017 Zaidi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and build upon your work non-commercially. Pluripotent stem cell technology: a promising remedy for hypopigmentation disorders Volume 2 Issue 5 - 2017 Kamal Uddin Zaidi, 1 Sharique AA, 2 Ayesha SA, 2 Vijay Thawani 1 1 Biotechnology Pharmacology Laboratory CSRD, Peoples University, India 2 Department of Biotechnology and Zoology, Saifa College of Science, India Correspondence: Kamal Uddin Zaidi, Biotechnology Pharmacology Laboratory CSRD, Peoples University, Bhopal, (M.P) 462037, India, Email Zaidi.kamal92@gmail.com Received: April 23, 2017 | Published: May 25, 2017 Abstract Pigment cells - epidermal melanocytes play physiological role in providing defense against harmful UV rays. Defect or deficiency of melanocytes and/or melanocyte stem cells can lead to pigmentation disorder such as vitiligo. The vitiligo forms white patches on the skin on the body. It is an autoimmune disease because the pigment inducing cells are damaged. Amongst its therapies, are UV light, cosmetic cover-up and corticosteroid local application. Human epidermis has been produced in vitro from mature epidermal stem cells of donors to provide the cell remedy. Source of pluripotent stem cells, either of embryonic origin or genetic reprogramming offers a substitute for epidermal cell treatment as these cells are immortal and pluripotent - theoretically capable of providing any number of cells of any desired phenotype. Keratinocytes and melanocytes resulting from pluripotent stem cells can be used for pathological modelling of genodermatoses allowing recognition of new disease- specific pharmacological treatment. We discuss the current approaches and imminent scenario of stem cells in hypopigmentation. Keywords: stem cell, melanocytes, vitiligo, melanin, pigmentation Journal of Stem Cell Research & Terapeutics Review article Open Access