Melanocyte Transplantation Research Articles

Emerging therapies and innovations in vitiligo management: a comprehensive review.

Vitiligo is a common skin disorder where melanocytes, the cells that produce skin pigment, are destroyed by the immune system, leading to white patches on the skin and mucous membranes. This condition affects 0.4% to 2.0% of the global population, with a higher prevalence in females and often beginning in childhood. In India, about 1% of the population is affected, particularly in northern regions, with a higher incidence in females and links to other autoimmune diseases. This review examines recent progress in understanding vitiligo and its treatment. It focuses on the genetic, autoimmune, and environmental factors involved in the disease and highlights new therapies, such as targeted molecular treatments and advanced repigmentation methods. Current research shows that oxidative stress and genetic predispositions contribute to the autoimmune destruction of melanocytes. Novel drug delivery systems, including liposomes, nanoemulsions, and nanostructured lipid carriers, have improved treatment effectiveness. Clinical trials are exploring new treatments like Ruxolitinib cream and melanocyte transplantation, while teledermatology is becoming useful for managing patients. Vitiligo also poses a significant economic burden due to its impact on patients' quality of life. Continued research is essential to develop better, more accessible treatments and reduce the economic impact of vitiligo.

Impact of Combined Phototherapy and Melanocyte Transplantation on Indicators of Vitiligo Activity.

To investigate the effect of phototherapy combined with melanocyte transplantation on the activity index of vitiligo. One hundred twenty patients with stable vitiligo were selected and divided into 2 groups: phototherapy group (n = 60) and phototherapy combined with melanocyte therapy group (n = 60). Patients' vitiligo activity scores before and 6 months after treatment, patients' skin pigmentation responses 6 months after treatment, and patients' new Koebner cases 6 months after treatment were compared. The expression of tyrosinase and Melan-A in the skin samples was analyzed by immunohistochemistry. The effect of skin surface repigmentation in the observation group was better than that in the control group (p < .05). The expression of tyrosinase and Melan-A in the observation group was higher than that in the control group (p < .05), indicating that the combined treatment could enhance the function of melanocytes. After 6 months of treatment, the incidence of the Koebner phenomenon in the observation group was lower than that in the control group (p < .05). The combination of phototherapy and melanocyte transplantation can obviously improve the activity index of vitiligo, slow down the spread of white spots, reduce the formation of new white spots, and reduce the occurrence of the Koebner phenomenon.

Target area treatment ratio of varied lesions in the cultured pure melanocyte transplantation repigmentation of vitiligo: Aretrospective study.

Autologous cultured pure melanocyte transplantation (CMT) can be utilized to treat stable vitiligo cases, but clinical data are insufficient to improve its efficacy. To evaluate the influence of various factors on the therapeutic effect of CMT, this single-center retrospective study enrolled stable vitiligo patients who underwent CMT between 2009 and2020. Univariate and multivariable analysis were used to determine the factors affecting the outcome of repigmentation. The study included 491 patients with long-term follow-up data (6-120 months). It was found that 69.7% of patients achieved an excellent re-color effect and 18.4% achieved a good re-color effect. There were statistically significant differences in pigmentation between patients with stable disease course, vitiligo type, and lesion site. Overall, a significant positive correlation between the target area treatment ratio of varied lesions and the percentage of repigmentation was found. CMT is effective and well tolerated in the treatment of stable vitiligo. Various factors, especially the target area treatment ratio of varied lesions, should be carefully assessed before using CMT. As the target area treatment ratio of varied lesions could further improve the post-operative repigmentation other than type of vitiligo. This clinic trial was approved by Hangzhou Third People's Hospital (number 2023KA015, national clinical record number MR-33-23-034502).

543 - Early repigmentation of stable vitiligo through point-of-care melanocyte transfer using non-cultured autologous skin cell suspension

Abstract Introduction Vitiligo is an acquired depigmenting skin condition characterized by the loss of skin pigmentation, impacting 0.5% to 2% of the global population.1–3 Vitiligo presents as distinct depigmented patches resulting from autoimmune melanocyte destruction. Individuals with visual vitiligo lesions often experience negative body image, diminished self-confidence, discomfort, and overall lower quality of life (QoL).4 While there are medical treatment options available, these can be associated with poor efficacy and low medication compliance.4 Residual lesions after treatment may require surgical intervention which allows for melanocyte transplantation from an area that is pigmented to one that is lacking functional melanocytes. Through a point-of-care device, a non-cultured autologous skin cell suspension (ACSC) can be prepared using a small skin sample; the ASCS contains healthy melanocytes and is immediately applied onto skin treated with ablative laser to aid in the repigmentation of affected areas. Objective The objective of this study was to evaluate the one-time application of ASCS, with a 1:20 donor to treatment site expansion ratio, for the safe and effective repigmentation of stable vitiligo lesions. Methods A randomized, within-subject controlled, central observer-blinded study was conducted to compare the clinical performance of laser ablation, ASCS, and NB-UVB to NB-UVB alone for repigmentation of stable vitiligo lesions in adults. Subjects received NB-UVB phototherapy on both ASCS-treated and controlled lesions as per recommended by the Vitiligo Working Group. Repigmentation of ASCS-treated and control lesions were categorized by a Central Review Committee (CRC) of blinded dermatologists as one of the following: 0%-25%, 26%-50%, 51%-79%, or 80-100%. The primary effectiveness endpoint was defined as the proportion of lesions achieving ≥80% repigmentation for ASCS-treated versus control areas at Week 24. Early regimentation was assessed at Weeks 4 and 12 as a post hoc analysis. Results A significantly higher proportion of the ASCS-treated areas (36.0%, n = 9) compared to control-treated areas (0.0%) attained ≥80% repigmentation at Week 24 (P = 0.012). At Week 4, 30.4% (n = 7/23) of ASCS-treated areas had ≥26% repigmentation compared to 4.3% (n = 1/23) in the control areas. At Week 12, 56.5% (n = 13/23) of ASCS-treated areas had ≥26% repigmentation compared to 21.7% (n = 5/23) in the control areas. At Week 24, 64% (n = 16/25) of ASCS-treated areas had ≥26% repigmentation compared to 28% (n = 7/25) in the control areas. Conclusion A one-time treatment of ASCS, with the addition of NB-UVB, can result in excellent repigmentation results by 24 weeks, with most subjects seeing ≥26% repigmentation as early as 4 to 12 weeks.

Early Repigmentation of Stable Vitiligo through Point-of-Care Melanocyte Transfer Using Non-Cultured Autologous Skin Cell Suspension

Introduction: Vitiligo is an acquired depigmenting skin condition characterized by the loss of skin pigmentation, impacting 0.5% to 2% of the global population.1,2 Vitiligo presents as distinct depigmented patches resulting from autoimmune melanocyte destruction. Individuals with visual vitiligo lesions often experience negative body image, diminished self-confidence, discomfort, and overall lower quality of life (QoL).3 While there are medical treatment options available, these can be associated with poor efficacy and low medication compliance.4 Residual lesions after treatment may require surgical intervention which allows for melanocyte transplantation from an area that is pigmented to one that is lacking functional melanocytes. Through a point-of-care device, a non-cultured autologous skin cell suspension (ACSC) can be prepared using a small skin sample; the ASCS contains healthy melanocytes and is immediately applied onto skin treated with ablative laser to aid in the repigmentation of affected areas. The objective of this study was to evaluate the one-time application of ASCS, with a 1:20 donor to treatment site expansion ratio, for the safe and effective repigmentation of stable vitiligo lesions. Methods: A randomized, within-subject controlled, central observer-blinded study was conducted to compare the clinical performance of laser ablation, ASCS, and NB-UVB to NB-UVB alone for repigmentation of stable vitiligo lesions in adults. Subjects received NB-UVB phototherapy on both ASCS-treated and controlled lesions as per recommended by the Vitiligo Working Group. Repigmentation of ASCS-treated and control lesions were categorized by a Central Review Committee (CRC) of blinded dermatologists as one of the following: 0%-25%, 26%-50%, 51%-79%, or 80-100%. The primary effectiveness endpoint was defined as the proportion of lesions achieving ≥80% repigmentation for ASCS-treated versus control areas at Week 24. Early regimentation was assessed at Weeks 4 and 12 as a post hoc analysis. Results: A significantly higher proportion of the ASCS-treated areas (36.0%, n = 9) compared to control-treated areas (0.0%) attained ≥80% repigmentation at Week 24 (P = 0.012). At Week 4, 30.4% (n = 7/23) of ASCS-treated areas had ≥26% repigmentation compared to 4.3% (n = 1/23) in the control areas. At Week 12, 56.5% (n = 13/23) of ASCS-treated areas had ≥26% repigmentation compared to 21.7% (n = 5/23) in the control areas. At Week 24, 64% (n = 16/25) of ASCS-treated areas had ≥26% repigmentation compared to 28% (n = 7/25) in the control areas. Conclusion: A one-time treatment of ASCS, with the addition of NB-UVB, can result in excellent repigmentation results by 24 weeks, with most subjects seeing ≥26% repigmentation as early as 4 to 12 weeks.

Comparative outcomes of autologous cultured melanocytes transplantation and non-cultured epidermal cell suspension transplantation in piebaldism patients: A retrospective study.

To compare the efficacy and safety of autologous cultured melanocytes transplantation (CMT) and non-cultured epidermal cell suspension transplantation (NCES) in the treatment of piebaldism. A retrospective study was conducted on 30 anatomically based lesions from nine piebaldism patients who underwent either CMT (n=7) or NCES (n=23) between 2018 and 2020. The extent of repigmentation and colour matching was evaluated in all recipient sites using a digital imaging analysis system. In addition, adverse effects have also been assessed by follow-up results. More than 75% repigmentation was achieved in 100% (7/7) and 60.9% (14/23) of the 30 lesions with the CMT and NCES, respectively. There were significant differences between the two methods in terms of repigmentation. The majority of patients had colour mismatches, and there was no discernible difference between the two surgical techniques. Adverse reactions rarely occurred. The present study suggested that autologous CMT may provide better repigmentation in piebaldism patients than NCES with no significant side effects.

Melanocyte transplantation to skin prepared by controlled PUVA-induced sunburn-like blistering for vitiligo treatment – A pilot clinical trial

Vitiligo is a common acquired disease of pigment loss. In lesions recalcitrant to non-invasive treatment, transplantation of cultured autologous melanocytes is an emerging choice. Conventionally, the recipient site is often prepared by laser-mediated or mechanical dermabrasion. Such preparation procedures have disadvantages including prolonged transplantation duration, long period for reepithelialization and potential scarring. We propose a method of preparing recipient sites by psoralen and controlled ultraviolet A (PUVA)-induced blistering followed by transplanting suspended melanocytes. We introduced this method in 10 patients with segmental vitiligo on their recipient site 3 to 5 days before transplantation and blistering developed in 2 to 3 days afterwards. On the day of transplantation, the blister roof could be peeled off easily without bleeding and the recipient site preparation could be completed in 20 min. The recipient site became reepithelialized within 1 week. Progressive repigmentation was observed for up to 6 months, with an average of 65.06% repigmentation in the recipient site without scarring at the end of follow-up. Hence, preparation of the recipient site by controlled PUVA-induced sunburn-like blistering can potentially facilitate melanocyte transplantation and prevent scarring.

Safety and Efficacy of Autologous Melanocyte/Keratinocyte Transplantation in Patients with Refractory Stable Vitiligo

Background: Vitiligo is a common depigmentation skin disease associated with significant psychosocial morbidity and profound effect on the quality of life. The treatment of vitiligo is still a major challenge in the field of dermatology. Currently, topical steroids, calcineurin inhibitors, ultraviolet phototherapy, surgery, and cultured and non-cultured epidermal melanocyte transplantation are used for the treatment of vitiligo. However, the effectiveness of these treatment modalities is limited by the lack of response, long-term treatment periods, high cost, and inevitable adverse effects. Objectives: In this study, we aimed to evaluate the efficacy of intraepidermal injection of autologous non-cultured melanocytes and keratinocytes as an alternative therapy for the refractory and stable (RS) vitiligo. Methods: The treatment procedure was performed on thirty-nine RS vitiligo patients. The autologous skin grafts obtained from the buttock area and epidermis were separated from dermis using dispase. Single-cell autologous melanocytes and keratinocytes were prepared from the epidermis by trypsin/ethylene diamine tetra acetic acid and injected at the concentration of 100–400 × 103 cells/cm2, intra-epidermally to the selected vitiligo lesions. Vitiligo re-pigmentation was monitored employing photography. Photographs were taken prior to and 2, 4, and 6 months after the cell transplantation. Improvement of the skin depigmentation was classified as follows: <25% as minimal response, 26–50% as moderate response, 51–75% as good response, and finally 76–100% as excellent response. Results: Cell infusion appeared to be safe as none of the patients exhibited any adverse effects. At the end of the sixth month follow-up period, of the treated patients, 12.8% demonstrated an excellent response, 36% exhibited a good response, and 51.2% showed a moderate to minimal response to the administered therapy. Obtained significant p value for Wilcoxon test over the checkpoints at 2nd, 4th, and 6th month (p = 0.03, 0.04, and 0.039, respectively) post-cell transplantation confirmed notable growing trend in the re-pigmentation. Conclusion: Our findings provide a strong support for the therapeutic efficacy of autologous non-cultured melanocytes and keratinocytes in patients with RS vitiligo.

1263 The application of melanocyte preparation and transplantation technology

1263 The application of melanocyte preparation and transplantation technology

585 Comparison of efficacy between cultured melanocyte transplantation and non-cultured epidermal cell suspension in stable vitiligo- a systematic review and meta-analysis

585 Comparison of efficacy between cultured melanocyte transplantation and non-cultured epidermal cell suspension in stable vitiligo- a systematic review and meta-analysis

535 The size and ratio of varied lesions in the cultured pure melanocyte transplantation repigmentation of vitiligo: A retrospective study

535 The size and ratio of varied lesions in the cultured pure melanocyte transplantation repigmentation of vitiligo: A retrospective study

The story of melanocyte: a long way from bench to bedside.

Skin is composed of major layers, namely a superficial epidermis and a deeper dermis. The color of skin is influenced by a number of pigments, including melanin, which is produced by cells called melanocytes. Most skin disorders are relatively benign, but a few, including melanomas, can be fatal. A number of more noticeable disorders, namely albinism and vitiligo, affect the appearance of the skin and its accessory organs. Vitiligo is associated with significant psycho-social morbidity and a major effect on quality of life. Topical steroids, calcineurin inhibitors, phototherapy and surgery are the most common treatments for melanoma. However, there are many patients who do not respond to any of these modalities. The transplantation of cultured or non-cultured melanocyte is the most important treatment for hypopigmentory disorders. This study aims at reviewing the history of melanocyte cultivation, and evaluating the effectiveness of transplantation of cultured cells. For this purpose, the authors examined the initial process of isolation, characterization, and transplantation of epidermal cells. This review, thus, summarizes the current understanding of the cutaneous pigmentary system from the start of synthesis in the pigment cells, along with the response of repigmentation. During the production of melanin, melanosomes are transferred to neighboring keratinocyte in order to form perinuclear melanin caps. The objective of this review is to analyze the melanocytes transplantation in the last century to date, and explore the methods epidermal cells can increase pigmentation in hypo-pigmented areas in skin disorders. Moreover, the focus is on the story of the melanocyte back to 1950s. In addition, prior systemic therapy was associated with a significant increase, based on combined additional therapy, achieving desired results and improved outcomes. Despite the short study of a long way of melanocyte assessment and following up patient treatment, results of the all reports confirmed the efficacy of the method used in the treatment of stable vitiligo patients, who did not respond to the common algorithms of non-invasive treatments.

Dermabrasion Versus Microneedling in Transplantation of Autologous Noncultured Melanocyte-Keratinocyte Cell Suspension in Patients With Vitiligo.

Autologous noncultured melanocyte-keratinocyte transplantation is one of the procedures used to treat stable vitiligo with varying reported results. Recipient site preparation is one of the variables that could affect repigmentation outcomes. To assess the effectiveness of transplanting autologous melanocyte-keratinocyte suspension in patients with stable vitiligo and to compare recipient site preparation using dermabrasion versus microneedling. From March 2020 to September 2022, this randomized comparative study included 40 patients with 40 stable vitiligo lesions managed by suspension transplants of melanocytes. Patients were divided into 2 groups: group A, where the recipient site was prepared using dermabrasion, and group B, which was done by microneedling. The assessment was performed 3 months after the treatment based on the degree of repigmentation (excellent, ≥90%; good, 50%-89%; fair, 20%-49%; and poor response, <20%). Both modalities resulted in effective repigmentation, but the dermabrasion group showed a statistically significant improvement and a satisfactory repigmentation rate. Autologous melanocyte transplantation is a safe and effective treatment method for stable vitiligo lesions that have not responded to other therapies. When compared with microneedling, dermabrasion produced better outcomes for recipient site preparation.

Transplantation of autologous epidermal melanocyte-keratinocyte cells suspension for cell therapy of vitiligo: Aclinical evaluation and biometric assessment.

Among several surgical treatments, the use of transplantation of epidermal cultured melanocytes or melanocytes-keratinocytes cell suspension has gained many researchers and dermatologists' attention as a new technique for the treatment of vitiligo. The present study aimed to transplant autologous epidermal melanocytes-keratinocytes cell suspension for the treatment of vitiligo. In this study, 15 volunteer patients aged between 18 and 45 years old were studied. The autologous melanocytes-keratinocytes cell suspension was then transplanted to the region after dermabrasion. The included patients were evaluated by VisioFace, MPA9, and Skin Scanner-DUB once before and 1, 2, and 6months after the transplantation, while the extents of stainability and changes in the transplanted region were recorded. The color contrast between the lesion and normal skin significantly decreased after 1, 2, and 6months of the melanocytes transplantation compared with the pre-procedure (13.8 ± 0.45 before vs. 12.9 ± 0.43, 12.2 ± 0.45, and 10.2 ± 0.34 at months 1, 2, and 6, p < 0.001). Furthermore, melanin index significantly increased six months after cell transplantation compared to the pretreatment (168.3 ± 4.22 vs. 130.5 ± 3.98, p < 0.001). Transplantation of melanocytes cells with dermabrasion can be effective on vitiligo improvement, so it is recommended.

Review. The story of melanocyte: long way from bench to bedside

Skin is composed of major layers, a superficial epidermis and a deeper dermis. The color of skin is influenced by a number of pigments, including melanin. Melanin is produced by cells called melanocytes. Most skin disorders are relatively benign, but a few, including melanomas, can be fatal. A couple of the more noticeable disorders, namely albinism and vitiligo, affect the appearance of the skin and its accessory organs. Vitiligo is associated with significant psychosocial morbidity and profound effect on quality of life. Topical steroids, calcineurin inhibitors, phototherapy and surgery are most common treatments. However, there are many patients who do not respond to any of these modalities. The transplantation of cultured or non-cultured melanocyte is the most important treatment for hypopigmentory disorders. In this study, we are going to assess the history of melanocyte cultivation and evaluate the effectiveness of transplantation cultured cells. We examined the beginning process of isolation, characterization, and transplantation of epidermal cells. This review, summarize our current understanding of the cutaneous pigmentary system from the start of synthesis in the pigment cells, along with the response of repigmentation. During the production of melanin, melanosomes are transferred to neighboring keratinocyte in order to form perinuclear melanin caps. The objective of this review is to analyze the melanocytes transplantation in the last century up to now, and how epidermal cells can increase pigmentation in hypo-pigmented areas in skin disorders. Also, we focus on the story of the melanocyte back to 1950. In addition, prior systemic therapy was associated with a significant increase significant increase based on combined additional therapy, achieving desired results and improved outcomes. Despite the short study of a long way of melanocyte assessment and follow up patient's treatment, results of the all reports were confirmed the efficacy of the used method in the treatment of stable vitiligo who did not respond to the common algorithms of non-invasive treatments.

Combination of epidermal keratinocyte-melanocyte cells suspension and microneedling: Safe surgical approach in vitiligo.

Vitiligo is a skin disease that is associated with impaired skin immune systems and pigment degradation in skin melanocyte cells. Despite the significant impact of the disease on the quality of life of patients, treatment of the disease using an effective method such as the transplantation of uncultivated melanocytes was considered by researchers around the world. The goal of this research was to use microneedling to transplant epidermal keratinocyte-melanocyte cells suspension for the treatment of vitiligo patients. In this study, 15male and female vitiligo in face region patients aged 18-45years were studied. In this study, melanocyte-keratinocyte cells suspension was sprayed. Patients underwent microneedling treatment after spraying the cells. Before and after transplantation, patients were biometrically examined, and the quantity of pigmentation and changes in the transplanted region were documented. Statistical software was used to examine the results. The color difference between the lesion area and normal skin in one, two, and six months after treatment with cell suspension was significantly reduced compared with before treatment (by 48.95%). Moreover, the amount of melanin was significantly increased 6months after treatment compared with before treatment (129.8±4.16 vs. 195.2±3.54, p=0.000). A significant decrease in skin brightness in the skin of the lesion area was observed compared with normal skin, 6months after treatment compared with before treatment (43.7±1.44 vs. 27.9±1.24, p=0.000). Epidermal keratinocyte-melanocyte cells suspension in combination with microneedling could be considered as an effective treatment of vitiligo.

Repigmentation by combined narrow‑band ultraviolet B/adipose‑derived stem cell transplantation in the mouse model: Role of Nrf2/HO‑1‑mediated Ca2+ homeostasis.

Vitiligo is a depigmentation disease commonly seen in clinical practice, mainly involving loss of functional epidermal pigment cells and hair follicle melanocytes. Narrow-band ultraviolet B (NB-UVB) has emerged as the first choice of treatment for vitiligo, but long-term exposure may have serious consequences. Recently, it was reported that adipose-derived stem cells (ADSCs) improve melanocyte growth and the efficacy of melanocyte transplantation. The present study aimed to examine the efficacy of NB-UVB/ADSC-transplantation combined therapy on a mouse vitiligo model and explore the underlying mechanisms by focusing on endoplasmic reticulum stress and cellular calcium (Ca2+) homeostasis. Vitiligo mice models were established by applying 40% monobenzone (MBZ) cream twice daily and treated with NB-UVB/ADSC combination therapy. Some treated mice were also given ML385, a nuclear factor erythroid 2 like 2 (Nr2) inhibitor. Histopathological changes were evaluated using a depigmentation evaluation score and observed with hematoxylin and eosin staining on skin tissues. ELISA was used to measure diagnostic markers in plasma. Flow cytometric assay was performed to quantify CD3+, CD4+ and CD8+ levels. Expression levels of associated proteins were detected with western blot and immunofluorescence. Treatment of mice with MBZ-induced depigmentation patches on the skin was accompanied with loss of redox balance and disruption of cellular Ca2+ homeostasis. Oxidative stress and Ca2+ unbalancing were improved after the mice were treated by NB-UVB/ADSCs transplantation combination therapy. ML385, strongly negated the protective effect of NB-UVB/ADSC transplantation combination therapy, indicating the critical role of Nr2 signaling. The findings improved the understanding of the pathogenesis of vitiligo and will guide future development of therapeutic strategies against it.

CXCL9 as a key biomarker of vitiligo activity and prediction of the success of cultured melanocyte transplantation

This study aimed to investigate the potential biomarkers of vitiligo by evaluating the disease activity and curative effect of autologous cultured pure melanocyte transplantation (CMT) on patients. Altogether, 36patients with stable vitiligo were treated with CMT. Blister fluid samples were collected from patients with stable vitiligo. Patients with active vitiligo were matched with healthy controls. The chemokine levels in the serum and blister fluid samples were measured using Luminex. The curative effect on patients with stable vitiligo was evaluated 6 months after treatment. Treatment responses were defined according to the extent of repigmentation as effective (if 50% or more repigmentation was achieved) or ineffective (if less than 50% or worse repigmentation was achieved). Patients received re-transplantation if the initial treatment was ineffective. The levels of C-X-C motif chemokine ligand (CXCL)9 and CXCL10 in blister fluid samples were significantly lower in stable patients than in active participants. Receiver operating characteristic analysis revealed that the levels of CXCL9 and CXCL10 were sensitive and specific in diagnosing active vitiligo. Further, 65.6% (21/32) of patients who received CMT had effective treatment responses. The high CXCL9 level in the blister fluid was a significant predictor of ineffective treatment responses. The treatment response was significantly enhanced after treatment. Four patients with ineffective treatment responses received anti-inflammatory treatment and re-transplantation. The CXCL9 and CXCL10 levels in the blister fluid were related to the presence of active vitiligo. Also, the CXCL9 level was a predictor of the effectiveness of CMT in treating vitiligo.

Donor to recipient ratios in the surgical treatment of vitiligo and piebaldism: a systematic review.

Stabilized vitiligo resistant to conventional therapy (e.g. segmental vitiligo) and piebaldism lesions can be treated with autologous cellular grafting techniques, such as non‐cultured cell suspension transplantation (NCST) and cultured melanocyte transplantation (CMT). These methods are preferred when treating larger surface areas due to the small amount of donor skin needed. However, the donor to recipient expansion ratios and outcomes reported in studies with cellular grafting vary widely, and to date, no overview or guideline exists on the optimal ratio. The aim of our study was to obtain an overview of the various expansion ratios used in cellular grafting and to identify whether expansion ratios affect repigmentation and colour match. We performed a systematic literature search in MEDLINE and EMBASE to review clinical studies that reported the expansion ratio and repigmentation after cellular grafting. We included 31 eligible clinical studies with 1591 patients in total. Our study provides an overview of various expansion ratios used in cellular grafting for vitiligo and piebaldism, which varied from 1:1 up to 1:100. We found expansion ratios between 1:1 and 1:10 for studies investigating NCST and from 1:20 to 1:100 in studies evaluating CMT. Pooled analyses of studies with the same expansion ratio and repigmentation thresholds showed that when using the lowest (1:3) expansion ratio, the proportion of lesions achieving >50% or >75% repigmentation after NCST was significantly better than when using the highest (1:10) expansion ratio (χ 2 P = 0.000 and χ 2 P = 0.006, respectively). Less than half of our included studies stated the colour match between different expansion ratios, and results were variable. In conclusion, the results of our study indicate that higher expansion ratios lead to lower repigmentation percentages after NCST treatment. This should be taken into consideration while determining which expansion ratio to use for treating a patient.

Innovative Technique for Securing Autologous Melanocyte-keratinocyte Cell Transplant (MKCT) Suspension in Stable Vitiligo.

Autologous cultured melanocyte transplantation is a safe and effective cellular regenerative surgical treatment modality for the lesions of stable vitiligo. Research continues to improve the efficacy of cell transplants by refining the procedure. The method of dressing used to secure the cell suspension over the treated site is vital in deciding the extent of repigmentation. The authors propose a simple modification in the dressing technique, which provides better graft adherence and results in uniform repigmentation, especially on challenging areas such as joints and other curved body surfaces.