title: Regulation of cutaneous pigmentation by titration of human melanocytes in cultured skin substitutes grafted to athymic mice.
abstract: Pigmentation of healed cultured skin substitutes in burn patients is frequently irregular and unpredictable which compromises solar protection and the patient's self-image. To address these morbidities, human fibroblasts were inoculated on a collagen-glycosaminoglycan substrate followed 1 day later by the addition of keratinocytes at 1.1 x 10(6)/cm2 combined with either 0, 1.1 x 10(2), 1.1 x 10(3), or 1.1 x 10(4) melanocytes/cm2. The skin substitutes were incubated in vitro for 3 weeks and grafted to athymic mice. In vitro, the number of L-Dopa-positive melanocytes in the skin substitutes increased proportionately to the number of melanocytes inoculated. The melanocytes localized to the basal epidermis when labeled for MEL-5. The skin substitutes with 1.1 x 10(4) melanocytes/cm2 were significantly darker than other groups in vitro by chromameter evaluation. By 12 weeks after grafting, the cultured skin ranged from no pigment in the control group, to 75% pigmented area in the 1.1 x 10(3) melanocytes/cm2 group, to complete pigmentation in the 1.1 x 10(4) melanocytes/cm2 group. In vivo, the mean chromameter values were significantly darker for the grafts with 1.1 x 10(3) and 1.1 x 10(4) melanocytes/cm2. These results suggest that complete restoration of cutaneous pigmentation can be accomplished by addition of between 0.1 and 1.0 x 10(4) melanocytes/cm2 to skin substitutes.
authors.affiliation: Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA.
authors.forename: Viki B
authors.initials: VB
authors.lastname: Swope
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Supp
authors.forename: Steven T
authors.initials: ST
authors.lastname: Boyce
mesh_terms: D000818:Animals; D002056:Burns / Q000150:complications* / Q000473:pathology / Q000601:surgery*; D002452:Cell Count; D002648:Child; D004195:Disease Models, Animal; D006801:Humans; D008297:Male; D008544:Melanocytes / Q000473:pathology / Q000637:transplantation*; D051379:Mice; D008819:Mice, Nude; D009924:Organ Culture Techniques; D010859:Pigmentation Disorders / Q000209:etiology* / Q000473:pathology / Q000601:surgery*; D016038:Skin Transplantation / Q000009:adverse effects*; D017768:Skin, Artificial / Q000009:adverse effects*; D013997:Time Factors; D017186:Titrimetry