Surgical techniques for vitiligo: a review

Differentiation of cultured hair follicle neural crest stem cells into functional melanocytes

Many autologous melanocytes are required for surgical treatment of depigmentation diseases such as vitiligo. However, primary cultured melanocytes have a limited number of in vitro passages. The production of functional epidermal melanocytes from stem cells provides an unprecedented source of cell therapy for vitiligo. This study explores the clinical application of melanocytes induced by hair follicle neural crest stem cells (HFNCSCs). This study established an in vitro differentiation model of HFNCSCs into melanocytes. Results demonstrate that most differentiated melanocytes expressed the proteins C-KIT, MITF, S-100B, TYRP1, TYRP2, and tyrosinase. The HFNCSC-derived melanocytes were successfully transplanted onto the dorsal skin of mice and survived in the local tissues, expressing marker protein of melanocytes. In conclusion, HFNCSCs in mice can be induced to differentiate into melanocytes under specific conditions. These induced melanocytes exhibit the potential to facilitate repigmentation in the lesion areas of vitiligo-affected mice, suggesting a promising avenue for therapeutic intervention.

Through a New Lens: Skin-Grafted Free Flaps and Objective Facial Skin Color Matching

Background: Head and neck ablative surgery can impose aesthetic disfigurement, particularly when severe color mismatch exists between native and reconstructed facial skin. To date, the accuracy, objectivity, and modifiability of facial skin color matching remains poorly understood. Objective: To measure skin color match outcomes after head and neck reconstruction using handheld colorimetry. Methods: Patients undergoing complex head and neck reconstruction involving facial skin were included. A variety of skin paddle donor sites were studied, including split-thickness skin graft (STSG) placement over myocutaneous or adipofasciocutaneous free flaps after de-epithelization. Skin color match (deltaE) was measured during follow-up using a handheld colorimeter. Results: Forty-seven patients were included, with median age 69. The most common flap type was the anterolateral thigh (n = 31, 66%). Twenty patients underwent STSG to the skin paddle. DeltaE measurements among the patients with STSGs demonstrated better color match (lowest deltaE), compared with patients with unaltered skin paddles (3.4 ± 1.0 vs. 6.5 ± 2.5, p < 0.0001). Conclusion: We found the use of STSGs over de-epithelialized myogenous or adipofasciocutaneous flaps improves color match, as measured by handheld colorimetry.

Worldwide expert recommendations for the diagnosis and management of vitiligo: Position statement from the international Vitiligo Task Force-Part 2: Specific treatment recommendations

BACKGROUND

The treatment of vitiligo can be challenging. Up-to-date agreed consensus recommendations on the use of topical and systemic therapies to facilitate the clinical management of vitiligo are currently lacking.

OBJECTIVES

To develop internationally agreed-upon expert-based recommendations for the treatment of vitiligo.

METHODS

In this consensus statement, a consortium of 42 international vitiligo experts and four patient representatives participated in different online and live meetings to develop a consensus management strategy for vitiligo. At least two vitiligo experts summarized the evidence for different topics included in the algorithms. A survey was then given to a core group of eight experts to resolve the remaining issues. Subsequently, the recommendations were finalized and validated based on further input from the entire group during two live meetings.

RESULTS

The recommendations provided summarize the latest evidence regarding the use of topical therapies (steroids, calcineurin inhibitors and Jak-inhibitors) and systemic therapies, including steroids and other systemic immunomodulating or antioxidant agents. The different modalities of phototherapies (NB-UVB, photochemotherapy, excimer devices and home phototherapy), which are often combined with other therapies, are also summarized. Interventional approaches as well as depigmentation strategies are presented for specific indications. Finally, the status of innovative and targeted therapies under development is discussed.

CONCLUSIONS

This international consensus statement culminated in expert-based clinical practice recommendations for the treatment of vitiligo. The development of new therapies is ongoing in vitiligo, and this will likely improve the future management of vitiligo, a disease that still has many unmet needs.

S1 Guideline: Diagnosis and therapy of vitiligo

Vitiligo is a common skin disorder characterized by immune-mediated destruction of melanocytes. Non-segmental vitiligo, the most common clinical subtype, has usually a chronic course and often results in significant psychosocial consequences for the affected patient. Early recognition, awareness of comorbidity, precise assessment of disease extent and activity, evaluation of impairment of quality of life as well as rapid initiation of treatment based on currently available evidence-based therapies are crucial cornerstones in the management of vitiligo. This S1 guideline helps German dermatologists to better diagnose and treat vitiligo.

Epidermal Stem Cells in Wound Healing and Regeneration

Skin stem cells distributed in the basal layer of the epidermis and hair follicles are important cell sources for skin development, metabolism, and injury repair. At present, great progress has been made in the study of epidermal stem cells at the cellular and molecular levels. Stem cell transplantation is reported to promote skin healing, endothelial cell transformation, and vascular formation. Local stem cells can also be transformed into keratinocytes, sebaceous gland, and other skin-associated tissues. However, the mechanism of action of epidermal stem cells on wound healing and regeneration is not completely clear. This review is aimed at briefly summarizing the biological characteristics of epidermal stem cells and their clinical application in wound healing and tissue regeneration. It further discussed the mechanism of action and the development direction in the future.

Tracking keratinocytes and melanocytes using carboxyfluorescein hydroxysuccinimidyl ester staining

Introduction

The treatment of burn wounds and hypopigmentation conditions often require autologous transplantation of keratinocytes and melanocytes. Tracking transplanted cells to ascertain their contribution to tissue recapitulation presents a challenge. This study demonstrates a methodology based on passive staining with carboxyfluorescein hydroxysuccinimidyl ester (CFSE) that enables localization of cells in tissue sections to investigate the fate of transplanted cells in wound re-epithelialisation.

Methods

Viability and migration of CFSE-stained keratinocytes and melanocytes were investigated using viability staining and scratch assays, while proliferation of cells was measured using flow cytometry. In addition, CFSE-stained keratinocytes and melanocytes were transplanted to a human ex vivo wound model, either in suspension, or with the aid of macroporous gelatine microcarriers. Wounds were analysed seven, 14 and 21 days post transplantation using cryosectioning and fluorescence microscopy. Sections from wounds with transplanted co-cultured keratinocytes and melanocytes were stained for pancytokeratin to distinguish keratinocytes.

Results

CFSE-staining of keratinocytes and melanocytes did not affect the viability, migration or proliferation of the cells. Transplanted cells were tracked in ex vivo wounds for 21 days, illustrating that the staining had no effect on wound re-epithelialisation. In conclusion, this study presents a novel application of CFSE-staining for tacking transplanted primary human keratinocytes and melanocytes.

Plasma & urinary catecholamines & urinary vanillylmandelic acid levels in patients with generalized vitiligo

Background & objectives

Vitiligo is an acquired skin disease characterized by depigmented areas of the skin. Increased release of catecholamines from autonomic nerve endings in microenvironment of melanocytes in affected skin might be involved in the aetiopathogenesis of vitiligo. Levels of catecholamines are considered as being related to onset or worsening of the disease. Therefore, in this study, the role of catecholamines was evaluated in mapping disease stability and outcome of vitiligo patients undergoing melanocyte transfer.

Methods

In this study, circulatory and urinary levels of catecholamine (CA) and vanillylmandelic acid (VMA) were determined in 45 individuals (30 vitiligo patients and 15 healthy controls) using ELISA.

Results

A significant increase for plasma and urinary catecholamines along with VMA was observed as compared to healthy controls. When the pre- and post-intervention levels were analyzed in responders and non-responders, respectively, only dopamine showed significant decline in urine, rest of the molecules in plasma as well as urine showed non-significant decline except VMA which showed insignificant increase.

Interpretation & conclusions

Levels of plasma/urinary epinephrine, and plasma dopamine, could not be established as biomarkers for disease stability or successful outcome of autologous melanocyte transfer in generalized vitiligo patients. However, dopamine (urine) might be of help in determining the stability in patients with generalized vitiligo undergoing melanocyte transfer. Further studies need to be done on a large sample of patients to confirm our findings.

Flavonoids as adjuvant in psoralen based photochemotherapy in the management of vitiligo/leucoderma

Vitiligo is a disorder characterized by the decrease in melanin pigment of skin. This depigmenting disorder has prevalence among worldwide, irrespective of age and sex. There is an existence of different treatment modalities for the management of vitiligo. But irrespective of treatment methods, the main drawback in the management of vitiligo is the occurrence of side effects during the implication of treatment. Among the treatment modalities, photochemotherapy seems to be the better choice of treatment for vitiligo. Photochemotherapy involves the usage of UV rays for photoactivation of the drug to cause photosensitization of skin which in turn leads to repigmentation. The main aim of the study is to develop novel combination strategy of lipid based nanoemulsion gel for the treatment of leucoderma using trimethylpsoralen and flavonoid. We assume that if this hypothesis of combination therapy proves successful it can be used as an additional novel treatment strategy in the management of vitiligo.

Artificial Pigmented Human Skin Created by Muse Cells

The skin composes physiological and chemical barrier and renews skin component cells throughout the human life. Melanocytes locate in the basal layer of the epidermis and produce melanin to protect the skin from ultraviolet. Melanin plays key roles in determining human skin and hair color. Melanocyte dysfunction observed in albinism and vitiligo not only causes cosmetic problems but also increases risk of skin cancer. As rejuvenate therapy, embryonic stem (ES) cells and induced pluripotent stem (iPS) cells have been reported to generate melanocytes. Other than ES and iPS cells, human skin tissues maintain pluripotent stem cells, named multilineage-differentiating stress-enduring (Muse) cells. We employ Muse cells isolated from human fibroblasts and adipose tissue to differentiate into melanocytes (Muse-MC). Muse-MC express melanocyte-related molecules, such as tyrosinase and DCT, and show tyrosinase activity. We also succeeded to differentiate Muse cells into fibroblasts and keratinocytes and created three-dimensional (3D) reconstituted skin with Muse cell-derived melanocytes, fibroblasts, and keratinocytes. The 3D reconstituted skin of Muse cell-derived cells coordinately showed epidermis layers and Muse-MC localized in the basal layer of the epidermis. Thus Muse cells in the human skin can be a source of rejuvenation medicine for the skin reconstruction.

Cultured epidermal stem cells in regenerative medicine

Transplantation of cultured epidermal cell sheets (CES) has long been used to treat patients with burns, chronic wounds, and stable vitiligo. In patients with large area burns this can be a life-saving procedure. The ultimate goal, however, is to restore all normal functions of the skin and prevent scar formation. Increased focus on the incorporation of epidermal stem cells (EpiSCs) within CES transplants may ultimately prove to be key to achieving this. Transplanted EpiSCs contribute to restoring the complete epidermis and provide long-term renewal.Maintenance of the regenerative potential of EpiSCs is anchorage-dependent. The extracellular matrix (ECM) provides physical cues that are interpreted by EpiSCs and reciprocal signaling between cells and ECM are integrated to determine cell fate. Thus, the carrier scaffold chosen for culture and transplant influences maintenance of EpiSC phenotype and may enhance or detract from regenerative healing following transfer.Long-term effectiveness and safety of genetically modified EpiSCs to correct the severe skin blistering disease epidermolysis bullosa has been shown clinically. Furthermore, skin is gaining interest as an easily accessible source of adult epithelial stem cells potentially useful for restoration of other types of epithelia. This review highlights the role of EpiSCs in the current treatment of skin injury and disease, as well as their potential in novel regenerative medicine applications involving other epithelia.

Bioreactor Microcarrier Cell Culture System (Bio-MCCS) for Large-Scale Production of Autologous Melanocytes

Restoration of cutaneous pigmentation can be achieved in stable vitiligo by autologous cultured melanocyte transplantation. It was the goal of this study to construct a bioreactor microcarrier cell culture system (Bio-MCCS) to produce autologous melanocytes in large scale. In this Bio-MCCS, porcine gelatin microbeads were used as microcarriers, spinning bottle as fermented tank. Autologous melanocytes were able to attach to and proliferate on the gelatin microbeads in serum-free melanocyte medium in the Bio-MCCS, reaching up to 24-fold the cells seeded on day 15 (MTT assay). These autologous melanocytes cultured on gelatin microbeads could leave the microbeads and proliferate on the bottom of tissue culture flasks. Although Pluronic F68 has been widely used to protect animal cells from hydrodynamic stress in animal cell bioreactors, Pluronic F68 at a concentration of 0.25–1.0% showed no significant protective effects on the autologous melanocytes cultured on the microbeads and subjected to mechanical stress in the Bio-MCCS. This Bio-MCCS using porcine gelatin microbeads as microcarriers enabled large-scale production of autologous mela-nocytes, offering a potential treatment for large-area stable vitiligo by direct administration of the melanocytes cultured on the gelatin microbeads to the vitiliginous site.

Successful Treatment of Stable Vitiligo by Low-Density Cultured Autologous Melanocyte Transplantation Combined With Narrowband Ultraviolet B Therapy

BACKGROUND

Cultured autologous melanocyte transplantation (CMT) is an effective treatment for stable vitiligo, but the current method is time consuming and expensive because of the requirement of a large number of melanocytes.

OBJECTIVE

To assess the clinical effect of low-density CMT combined with narrowband ultraviolet B (NB-UVB) in treating stable vitiligo.

MATERIALS AND METHODS

The authors treated 8 patients with CMT at a low cell density (less than 2.5 × 10 cells/cm). Among them, 6 patients underwent NB-UVB therapy after CMT.

RESULTS

All the 6 patients treated with low-density CMT combined with NB-UVB obtained more than 90% repigmentation at the 1-year follow-up.

CONCLUSION

The authors' data suggest that low-density CMT combined with NB-UVB can be an effective form of surgical treatment for stable vitiligo.

A quantitative analysis of multilineage-differentiating stress-enduring (Muse) cells in human adipose tissue and efficacy of melanocytes induction

We have shown previously that multilineage-differentiating stress-enduring (Muse) cells in neonatal fibroblasts can differentiate into functional melanocytes. In this study, we quantitate Muse cells in adipose-mesenchymal stem cells (adipose-MSCs) of human subcutaneous tissue obtained from 11 subjects of various ages, and measured efficacy of melanocytes induction from Adipose-MSC-derived Muse cells (hASC-Muse cells). There was a statistically significant negative correlation between the age of donors and the numbers of adipose-MSCs recovered per g fat as well as the percentage of SSEA3+ cells in the adipose-MSC populations, but isolated hASC-Muse cells showed pluripotency and growth curves equally regardless the age of donors. Adipose-Muse cells sequentially expressed melanocyte-related genes including KIT, MITF, TYRP1 PMEL, DCT, melanocortin 1 receptor (MC1R), and TYR at a comparable level to melanocytes during 6-week culture. Parallel with MC1R expression, adipose-Muse cells increased melanin content by α-MSH stimulation. By quantitating the cell numbers recovered at each step, we found that 10g of adipose tissue could produce at least 2.5×10⁶ melanocytes after 6 weeks of culture. These studies suggest that induction of melanocytes from adipose-Muse is a novel approach to obtain sufficient numbers of melanocytes for clinical application and in vitro study of melanocyte differentiation.

Recipient site preparation for epidermal graft in stable vitiligo by a special fraise

BACKGROUND

The only approach used in the refractory lesions of stable vitiligo is the surgical supply of melanocytes. Suction Blistering Epidermal Graft is one of the most common and effective techniques. There are multiple modalities, including the motor-driven diamond fraise, for the preparation of recipient sites in suction blistering epidermal graft with different repigmentation rates and complications.

OBJECTIVES

To evaluate preparation of recipient site by a motor-driven dental lab finishing carbide bur.

METHODS

Sixty-one stable, depigmented lesions were selected in 14 patients (9 women and 5men), aged 16-29 years, of which 9, 3 and 2 had localized, generalized and segmental vitiligo, respectively. Recipient site was prepared by a motor-driven dental lab finishing carbide bur.

RESULT

Excellent repigmentation at the recipient site was observed in 53 out of 61 (86.9%) grafted lesions. Postinflammatory hyperpigmentation and perigraft halo were seen in 11 (18%) and 17 (27.9%) patients at the recipient site, respectively.

CONCLUSION

Using a motor-driven dental lab finishing carbide bur to prepare the recipient site of suction blistering epidermal graft technique is reliable and effective, removing only the depigmented epidermis in a simple and safe manner, even on complex-shaped lesions and scar-prone sites.

Potential of regenerative medicine for treatment of vitiligo patients

The article presents a review of publishes sources on the efficacy of methods such as tissue engineering and cellular transplantation of autologous melanocytes for treatment of vitiligo patients. The article describes general principles of treatment and particular features of current melanocyte transplantation methods.

Amniotic membrane as a scaffold for melanocyte transplantation in patients with stable vitiligo

Vitiligo is an acquired skin disease that significantly impacts the quality of life of patients. Medical treatment of vitiligo includes the use of melanocyte transplant, but the results are variable. We have treated 4 patients with either focal or generalized stable vitiligo using a graft of autologous melanocytes' culture on a denuded amniotic membrane (AM). A culture biopsy was obtained in every patient and grown in melanocytes' media for 10-14 days after which cells were transferred to a denuded AM and transplanted into the achromic lesions. Patients were followed for up to 6 months using clinical assessment of achromic lesions. Treated areas ranged between 4 cm(2) and 210.6 cm(2). Response to treatment was excellent in all patients with 90-95% repigmentation success rate. Our results demonstrate that transplantation of autologous melanocytes cultured on AM is a new, simple, and effective treatment for stable vitiligo.

Generation of melanocytes from induced pluripotent stem cells

Epidermal melanocytes play an important role in protecting skin from ultraviolet (UV) rays, and are implicated in a variety of skin diseases. Here, we developed an efficient method for differentiating induced pluripotent stem cells (iPSCs) into melanocytes. We first generated iPSCs from adult mouse tail-tip fibroblasts (TTFs) using retroviral vectors or virus-free piggyBac transposon vectors carrying murine Sox2, Oct3/4, cMyc and Klf4. The TTF-derived iPSC clones exhibited similar morphology and growth properties as mouse embryonic stem (ES) cells. The iPSCs expressed ES cell markers, displayed characteristic epigenetic changes and formed teratomas with all three germ layers. The iPSCs were used to generate embryoid bodies (EBs) and were then successfully differentiated into melanocytes by treatment with growth factors. The iPSC-derived melanocytes expressed characteristic melanocyte markers and produced melanin pigment. Electron microscopy showed that the melanocytes contained mature melanosomes. We manipulated the conditions used to differentiate iPSCs to melanocytes and discovered that Wnt3a is not required for mouse melanocyte differentiation. This report shows that melanocytes can be readily generated from iPSCs, providing a powerful resource for the in vitro study of melanocyte developmental biology and diseases. By inducing iPSCs without viruses, the possibility of integration mutagenesis is alleviated, providing iPSCs are more compatible for cell replacement therapies.

Generation of human melanocytes from induced pluripotent stem cells

Epidermal melanocytes play an important role in protecting the skin from UV rays, and their functional impairment results in pigment disorders. Additionally, melanomas are considered to arise from mutations that accumulate in melanocyte stem cells. The mechanisms underlying melanocyte differentiation and the defining characteristics of melanocyte stem cells in humans are, however, largely unknown. In the present study, we set out to generate melanocytes from human iPS cells in vitro, leading to a preliminary investigation of the mechanisms of human melanocyte differentiation. We generated iPS cell lines from human dermal fibroblasts using the Yamanaka factors (SOX2, OCT3/4, and KLF4, with or without c-MYC). These iPS cell lines were subsequently used to form embryoid bodies (EBs) and then differentiated into melanocytes via culture supplementation with Wnt3a, SCF, and ET-3. Seven weeks after inducing differentiation, pigmented cells expressing melanocyte markers such as MITF, tyrosinase, SILV, and TYRP1, were detected. Melanosomes were identified in these pigmented cells by electron microscopy, and global gene expression profiling of the pigmented cells showed a high similarity to that of human primary foreskin-derived melanocytes, suggesting the successful generation of melanocytes from iPS cells. This in vitro differentiation system should prove useful for understanding human melanocyte biology and revealing the mechanism of various pigment cell disorders, including melanoma.

Modified Procedure of Noncultured Epidermal Suspension Transplantation: Changes are the Core of Vitiligo Surgery

Epidermal cell suspensions are being increasingly used in the surgical management of vitiligo. The procedure suffers from several drawbacks such as high cost of the procedure, difficulty of procuring the reagents etc. We hereby describe modifications which allow the use of cheaper, more commonly available alternatives.

Treatment of upper- and lower-extremity vitiligo with epidermal grafts after CO2 laser resurfacing with systemic and topical steroids

Vitiligo is an acquired condition that presents as sharply demarcated white macules. It affects 1-2% of people of all races, regardless of gender or age. Although the disease does not have any systemic complications, it is of great concern, particularly in darker-skinned individuals. We treated 14 patients with vitiligo involving the upper and lower extremities. Surgical therapies were used in conjunction with medical therapy to achieve repigmentation after the disease was stabilized.

Current remedies for vitiligo

Vitiligo is a disorder with complex causes and is a type of autoimmune disease in which the immune system targets the body's own pigment cells and tissues. Our aim is to present an overall view of the current remedies widely adopted for the treatment of vitiligo. Medical treatments target the immune system, and try to reverse the destruction. The goal is to restore the skin's color by restoring healthy melanocytes to the affected area. Apart from melanocytes, vitiligo autoantigens appear also on other cells. Even though antibodies to pigment cells are not an agent of vitiligo, the most valuable contribution is that anti-melanocyte antibody reactivity can help in identifying relevant antigens. T cells from vitiligo skin are highly reactive towards melanoma cells and serve as an effective source to treat melanoma and stays as a solution for vitiligo. There have been many treatments to cure vitiligo such as use of steroid creams, PUVA (psoralen and ultraviolet A light), narrow band UVB (ultraviolet B), various surgical techniques, vitamin D analogues and pseudocatalase. These treatments are subjected for undesired side effects whereas some herbal and natural treatments act against the immune system with no side effects.

Vitiligo treatment options: An evolving scenario

Sequential displays of several treatment options for vitiligo have been scanned from the literature, and are presented here. A few of the medical modalities have been resigned to history, whereas others have become customary in clinical practice. There has also been a recent surge of interest in the surgical treatment of this disease. Accordingly, this has been appraised and summarized. Special attention has been given to prevalent medical modalities so that they may be effectively utilized by those currently in practice.

Suction blister epidermal grafts combined with CO2 laser superficial ablation as a good method for treating small-sized vitiligo

BACKGROUND

Despite the availability of various new methods to treat vitiligo, surgical methods offer rapid, simple, and safe ways for treating small-sized vitiligo.

OBJECTIVE

To evaluate the feasibility and efficacy in treating vitiligo using suction blister epidermal grafting (SBEG) combined with CO2 laser epidermal ablation.

METHODS

Forty patients with small, stable vitiligo were treated using SBEG combined with CO2 laser epidermal ablation and followed up for at least 6 months and up to 10 years.

RESULTS

Treatment outcomes were excellent for 32 patients (80%), good for four patients (10%), fair for three patients (7.5%), and poor for one patient (2.5%). No scar formation was observed in any patients. Location of the lesions was probably the most important factor in determining the outcomes of transplantation.

CONCLUSION

This study suggests that SBEG combined with CO2 laser ablation is a rapid, simple, and safe method to treat vitiligo, especially for patients with small and stable vitiliginous lesions.

Cellular grafts in management of leucoderma

Cellular grafting methods constitute important advances in the surgical management of leucoderma. Different methods such as noncultured epidermal suspensions, melanocyte cultures, and melanocyte-keratinocyte cultures have all been shown to be effective. This article reviews these methods.

Vitiligo: avaliação histológica e clínica após curetagem seqüencial

FUNDAMENTOS: Melanócitos amelanóticos inativos estão presentes no folículo piloso, constituindo reserva melanocítica no vitiligo. Procedimentos que provocam abrasão superficial da pele induzem a ativação e a migração de melanócitos do folículo piloso. OBJETIVO: Teve-se por objetivos avaliar: 1) o percentual médio do número de melanócitos em relação aos ceratinócitos na camada basal epidérmica e a presença de melanina à histopatologia; 2) a evolução clínica, após curetagem seqüencial em lesões de vitiligo. MÉTODOS: Foram avaliados 16 pacientes nos quais foi realizada seqüência de três curetagens superficiais a cada 30 dias, com biópsias pré-curetagem (controle) e 30 dias após cada curetagem. Coloração pela hematoxilina-eosina foi utilizada para contagem do percentual de melanócitos em relação aos ceratinócitos da camada basal epidérmica, e de Fontana-Masson para determinar a presença de melanina. A evolução clínica foi avaliada por documentação iconográfica. RESULTADOS: Observaram-se tendência ao aumento do percentual médio de melanócitos (p<0,10) e aumento estatisticamente significante da presença de melanina e de repigmentação cutânea (p<0,05) após a terceira curetagem. CONCLUSÕES: Uma seqüência de curetagens tende a elevar o percentual médio de melanócitos na camada basal epidérmica, induz a formação de grânulos de melanina e o aumento da repigmentação no vitiligo.

Subjective and Objective Evaluation of Noncultured Epidermal Cellular Grafting for Repigmenting Vitiligo

BACKGROUND

Noncultured epidermal cell transplantation in vitiligo permits the coverage of relatively large areas without culturing cells.

OBJECTIVE

To investigate the effectiveness of noncultured epidermal cell transplantation in treating stabilized vitiligo using objective and subjective evaluation methods.

METHODS

Noncultured autologous melanocytes and keratinocytes were grafted in a hyaluronic-acid-enriched suspension on superficially laser-abraded vitiligo lesions in 40 patients with refractory stable vitiligo (30 with generalized and 10 with localized vitiligo). The repigmentation was evaluated 3-12 months after grafting using a digital image analysis system. Furthermore the treatment was evaluated from the patients' point of view with the DLQI (Dermatology Life Quality Index) and a 'global assessment'.

RESULTS

The mean percentage of repigmentation, evaluated at the last follow-up visit, was 72% (median 84%), and a repigmentation of >or=70% was observed in 62% of patients. The best results were achieved in the neck and the presternal region. A subjective evaluation was performed in half of the subjects. The mean DLQI score at inclusion (6.95, SD = 6.68, n = 20) was significantly decreased after treatment (p = 0.013, mean 3.85, SD = 4.13, n = 20). The patients were satisfied with the achieved result, found it worthwhile to undergo the treatment and would choose it again.

CONCLUSION

According to both subjective and objective evaluation methods, noncultured epidermal cell transplantation is promising in patients with stable vitiligo.

Efficacy of autologous transplantation of noncultured epidermal suspension in two different dilutions in the treatment of vitiligo

BACKGROUND

Previous reports have shown the effectiveness of a basal layer cell suspension in the treatment of stable vitiligo; however, there has been no mention in the literature until now of the optimal number of melanocytes required in an autologous noncultured epidermal suspension for transplantation to obtain early and acceptable results.

METHODS

In this randomized prospective study, we compared the efficacy of two different dilutions to determine the optimum density of melanocytes required for transplantation to achieve early and cosmetically acceptable results. We enrolled 20 patients with stable vitiligo with a body surface area involvement of< 10%.

RESULTS

Fifty per cent of patients in Group A (where the recipient area transplanted was approximately three times the size of the donor area, and the density of melanocytes transplanted per square millimeter was approximately 231.60+/- 27.03) showed marked (> 75%), 20% moderate, 10% mild, and 20% minimal repigmentation (or no response). In Group B (where the recipient area was increased to five-fold the donor area), none of the patients showed marked, 10% showed moderate, 20% showed mild, and 70% showed either minimal or no repigmentation. The density of melanocytes transplanted in this group was 154.90+/- 27.65/mm(2). The extent of repigmentation was significantly greater (P< 0.05) in Group A than in Group B, and the density of melanocytes in the suspension was also significantly greater (P< 0.01) in Group A than in Group B.

CONCLUSION

We contend that the minimum number of melanocytes required to produce satisfactory repigmentation is probably in the range of 210-250/mm(2).

Use of the 308-nm excimer laser for psoriasis and vitiligo

The 308-nm excimer laser represents the latest advance in the concept of selective phototherapy. It emits a wavelength in the UV-B spectrum and thus shares the same indications as conventional phototherapy. Like other laser devices, the 308-nm excimer laser emits a monochromatic and coherent beam of light, can selectively treat a lesion while sparing surrounding healthy skin, and can deliver high fluencies. Clinicians have taken advantage of these properties to treat dermatologic disorders since 1997, with psoriasis and vitiligo attracting most attention. Initially, high fluencies (minimal erythemal dose, 8-16) were used, with excellent clinical results, to treat psoriasis vulgaris. The significance of side effects and the potential long-term carcinogenic risk associated with such fluencies have resulted in medium doses (about 3 minimal erythemal dose) being recommended, however. Interestingly, taking advantage of the selectivity of the laser, newer treatment protocols adapt the dose to the lesion and not to the minimal erythemal dose, as is the case for conventional phototherapies. Many prospective study series have also shown the efficacy and the good tolerance of the 308-nm excimer laser in the treatment of localized vitiligo. Induced rates of repigmentation seem to be higher than with narrowband UV-B. Moreover, the selectivity of the treatment prevents irradiation of healthy skin and limits unsightly tanning of surrounding skin. Aesthetically pleasing results are usually not achieved in extremities and bony prominences, which are not good indications for this technique. Combining the 308-nm excimer laser with 0.1% tacrolimus ointment has provided very interesting results, which need to be confirmed in larger series. The absence of actual data concerning the long-term risk for skin cancer after this treatment means that it should be considered with caution. Combination with topical steroids appears to be synergistic and potentially reduces long-term side effects; again, prospective data are lacking.

A chemically defined surface for the co-culture of melanocytes and keratinocytes

Patients with stable vitiligo can be helped surgically using transplantation of autologous cultured melanocytes, but there is a need for a culture methodology that is free from xenobiotic agents and for a simple way of delivering cultured melanocytes to the patient to achieve pigmentation with good wound healing. The aim of this study was to develop a chemically defined surface, suitable for the co-culture of melanocytes and keratinocytes which could be used in the future for the treatment vitiligo patients to achieve both restoration of pigmentation and good wound healing. Two keratinocyte growth media and two melanocyte growth media were compared; two of these were serum free. Cells were seeded on a range of chemically defined substrates (produced by plasma polymerisation of acrylic acid, allylamine or a mixture of these monomers) either as mono- or co-cultures. Melanocytes and keratinocytes attached and proliferated on both acid and amine substrates (without significant preferences), and co-cultures of cells proliferated more successfully than individual cultures. One media, M2, which is serum free, supported expansion of melanocytes and to a lesser extent keratinocytes on several plasma polymer substrates. In conclusion, these data indicate that a combination of a chemically defined substrate with M2 media allows serum-free co-culture of melanocytes and keratinocytes.

Autologous epidermal cultures and narrow-band ultraviolet B in the surgical treatment of vitiligo

BACKGROUND

Vitiligo is an acquired skin disorder with a great social impact. It can be successfully treated with autologous epidermal grafting.

OBJECTIVE

To evaluate the possibility of treating vitiligo by autologous grafting of epidermal cells and narrow-band ultraviolet B (UVB).

METHODS

Autologous epidermal cultures were prepared starting from small biopsies of normally pigmented skin. Cells were cultured on hyaluronic acid membranes using medium supplemented with patient's serum. Cell cultures were grafted onto laser-abraded depigmented areas. Patients underwent narrow-band UVB therapy 3 weeks after grafting.

RESULTS

Repigmentation of the grafted areas started 1 month after transplant and continued until 4 months after grafting. All patients were evaluated 3, 6, 12, and 18 months after grafting. At the 18-month follow-up, repigmentation was observed in 75% of patients with focal and segmental vitiligo and in 30% of patients with generalized vitiligo.

CONCLUSIONS

This therapy can be considered for the treatment of stable vitiligo (especially focal and segmental) resistant to standard therapies. Their results are encouraging from the clinical and esthetic point of view, although the treatment is costly and highly specialized.

Treatment of vitiligo by transplantation of cultured pure melanocyte suspension: analysis of 120 cases

BACKGROUND

Despite the availability of various medical treatments for vitiligo, a large percentage of patients fail to achieve satisfactory results. Surgical techniques offer a potential solution for patients with vitiligo who fail to respond to medical treatments.

OBJECTIVE

We evaluated the practicality in treating vitiligo by using cultured autologous pure melanocytes and investigated the different results among stable localized vitiligo, stable generalized vitiligo, and active generalized vitiligo.

METHODS

In all, 120 patients with vitiligo were treated with transplantation of autologous cultured pure melanocyte suspension after carbon-dioxide laser abrasion.

RESULTS

Patients with stable localized vitiligo experienced the highest percentage of excellent repigmentation with 84% achieving 90% to 100% coverage, followed by 54% of patients with stable generalized vitiligo, whereas only 14% of patients with active generalized vitiligo experienced good repigmentation. Age and sex of the patients, and size and location of the lesions, did not show significant influence on the results of transplantation.

CONCLUSION

Autologous cultured pure melanocyte suspension combined with carbon-dioxide laser abrasion is an effective treatment for patients with stable vitiligo who fail to respond to medical treatments, especially for those with stable localized vitiligo.

Photo(chemo) therapy for vitiligo

Vitiligo has always been difficult to treat. Several modes of treatment are available, but the therapeutic effect varies greatly, and rarely does one achieve complete repigmentation. One of the most efficient treatment methods is photo(chemo) therapy. Already in ancient Egypt, vitiligo lesions were treated with extracts of the Ammi maius plant followed by exposure to the sun. This principle is at the basis of the photochemotherapy or PUVA therapy, whereby UVA irradiations are given 2 h after administration of 8-methoxypsoralen, a photosensitizer. Another efficient treatment form is UVB phototherapy, particularly narrow-band UVB. This not only gives good therapeutic results but also has the advantage of eliminating the need for a photosensitizer. All these treatments must be applied for many months to be efficient. They can also be combined with various surgical skin-grafting techniques. A newer approach is targeted UVB phototherapy, whereby xenon-chloride lasers or monochromatic excimer light is used.

Autologous cellular suspensions and sheets in the treatment of achromic disorders: the need for future controlled studies

Transplantation techniques using cultured and noncultured keratinocyte and/or melanocyte suspensions or sheets have been reported as successful in inducing repigmentation in achromic epidermal diseases such as vitiligo and piebaldism. However, the role of a lot of variable factors in the transplantation procedure remains unclear. Occasionally control sites are included in the reported patient series. We point out the need for future controlled studies when performing transplantations of cellular suspensions and sheets. This approach will help to understand how these techniques induce repigmentation and may eventually indicate the essential requirements for successful results.