Vitiligo: characterization of melanocytes in repigmented skin after punch grafting. (4th August 2014)

• Record Type: Journal Article
• Authors: Kovacs, D.; Abdel‐Raouf, H.; Al‐Khayyat, M.; Abdel‐Azeem, E.; Hanna, M.R.; Cota, C.; Picardo, M.; Anbar, T.S.
• Is Part Of: Journal of the European Academy of Dermatology and Venereology. Volume 29:Number 3(2015:Mar.)
• Page Start: 581
• Page End: 590
• Publication Date: 2014-08-04
• Subjects: Dermatology -- Periodicals; Sexually transmitted diseases -- Periodicals; 616.5
• DOI: 10.1111/jdv.12647
• Languages: English
• ISSNs: 0926-9959

Abstract

<abstract abstract-type="main" id="jdv12647-abs-0001"> <title>Abstract</title> <sec id="jdv12647-sec-0001" sec-type="section"> <title>Background</title> <p>Punch grafting is a surgical technique mainly applied in therapy‐resistant, stable and circumscribed vitiligo.</p> </sec> <sec id="jdv12647-sec-0002" sec-type="section"> <title>Objective</title> <p>(i) To characterize in detail the features of the repigmented skin among punch grafts; and (ii) to correlate the <italic>ex vivo</italic> results with clinical data and punch grafting outcome.</p> </sec> <sec id="jdv12647-sec-0003" sec-type="section"> <title>Methods</title> <p>We evaluated by immunohistochemistry and image analysis the expression of a panel of specific melanocyte markers including HMB45, MITF, c‐kit, MART‐1 and TRP1, the proliferation marker Ki67 and the cell–cell adhesion molecule E‐cadherin in tissue samples collected from nine patients after punch grafting.</p> </sec> <sec id="jdv12647-sec-0004" sec-type="section"> <title>Results</title> <p>Cells positive for MITF, c‐kit, MART‐1 and TRP1 were detected in the repigmented skin of all biopsies, whereas no reactivity was observed for HMB45. Melanocytes were identified along the entire length of the sections, and their mature state was assessed by the immuno‐reactivity for the differentiation marker MART‐1, the absence of cells positively stained for Ki67 and by the co‐expression of c‐kit and TRP1, a marker of a differentiated and pigmented state. Clinically, smaller punch grafts aimed at repigmenting lesional areas on the face gave the faster clinical results with no side‐effects. Patients subjected to bigger punch grafts on the knee exhibited a longer repigmentation time and presented cobble stoning.</p> </sec> <sec id="jdv12647-sec-0005" sec-type="section"> <title>Conclusion</title> <p>Our results suggest that the repigmentation observed in the areas between the grafts is due to the activation of the melanocytes located in the donor sites. These cells start to horizontally migrate towards the lesional skin thanks to successively the enlargement of intercellular spaces in relation to a decrease of E‐cadherin reactivity and the up‐modulation of pro‐melanogenic mediators. Production and transfer of melanin in the surrounding keratinocytes and their persistence were assessed by the reactivity for MITF, c‐kit, MART‐1 and TRP1 but not for the pre‐melanosome marker (HMB45).</p> </sec> </abstract>