Efficacy of Transplantation of Combination of Noncultured Dermal and Epidermal Cell Suspension vs Epidermal Cell Suspension Alone in Vitiligo: A Randomized Clinical Trial

Conventional suspension delivery versus tattooing pen-assisted suspension delivery in non-cultured epidermal cell suspension procedure for vitiligo: A randomized controlled trial

Non-cultured epidermal suspension (NCES) is one of the most widely used surgical therapy for stable vitiligo patients in which recipient size preparation plays an important role in the outcome of NCES. The primary objective is to evaluate and compare the efficacy and safety of conventional suspension delivery after manual dermabrasion (CSMD) versus tattooing pen-assisted suspension delivery (TPSD) in NCES. Paired vitiligo units (VU) in 36 patients, matched with respect to size and location were divided into two groups. The VU in Group 1 underwent suspension delivery by CSMD while the VU in Group 2 underwent same by TPSD. All the VU were followed up at regular intervals until 24 weeks. At the end of 24 weeks, 31 VU (86.1%) in Group 1 achieved >75% repigmentation which was significantly higher (p = .02, chi-square test) as compared to 22 VU (61.1%) in Group 2. The color matching in both the groups VU was also comparable (p = .84, chi-square test). The patient global assessment (PGA) was significantly higher in Group 1 VU as compared to Group 2. Treatment response in terms of repigmentation and PGA was significantly better in VU treated with CSMD as compared to TPSD. Recipient site complications were seen more commonly in Group 1 VU as compared to Group 2. Perilesional halo at the recipient site was seen in none of the VU in Group 2 which was significantly lower than 6 VU in Group 1 than (p = .02, chi-square test). Better results may be possible with technical improvisations in tattooing pen needle diameter and depth of penetration.

The efficacy and safety of autologous epidermal cell suspensions for re-epithelialization of skin lesions: A systematic review and meta-analysis of randomized trials

BACKGROUND

Successful usage of autologous skin cell suspension (ASCS) has been demonstrated in some clinical trials. However, its efficacy and safety have not been verified. This latest systematic review and meta-analysis aim to examine the effects of autologous epidermal cell suspensions in re-epithelialization of skin lesions.

METHODS

Relevant articles were retrieved from PubMed, Embase, Cochrane Database, Web of Science, International Clinical Trials Registry Platform, China National Knowledge Infrastructureris, VIP Database for Chinese Technical Periodicals and Wanfang database. The primary output measure was the healing time, and the secondary outputs were effective rate, size of donor site for treatment, size of study treatment area, operation time, pain scores, repigmentation, complications, scar scale scores and satisfaction scores. Data were pooled and expressed as relative risk (RR), mean difference (MD) and standardized mean difference (SMD) with a 95% confidence interval (CI).

RESULTS

Thirty-one studies were included in this systematic review and meta-analysis, with 914 patients who received autologous epidermal cell suspensions (treatment group) and 883 patients who received standard care or placebo (control group). The pooled data from all included studies demonstrated that the treatment group has significantly reduced healing time (SMD = -0.86; 95% CI: -1.59-0.14; p = 0.02, I2 = 95%), size of donar site for treatment (MD = -115.41; 95% CI: -128.74-102.09; p<0.001, I2 = 89%), operation time (MD = 25.35; 95% CI: 23.42-27.29; p<0.001, I2 = 100%), pain scores (SMD = -1.88; 95% CI: -2.86-0.90; p = 0.0002, I2 = 89%) and complications (RR = 0.59; 95% CI: 0.36-0.96; p = 0.03, I2 = 66%), as well as significantly increased effective rate (RR = 1.20; 95% CI: 1.01-1.42; p = 0.04, I2 = 77%). There were no significant differences in the size of study treatment area, repigmentation, scar scale scores and satisfaction scores between the two groups.

CONCLUSION

Our meta-analysis showed that autologous epidermal cell suspensions is beneficial for re-epithelialization of skin lesions as they significantly reduce the healing time, size of donar site for treatment, operation time, pain scores and complications, as well as increased effective rate. However, this intervention has minimal impact on size of treatment area, repigmentation, scar scale scores and satisfaction scores.

The Role of Oxidative Stress in Vitiligo: An Update on Its Pathogenesis and Therapeutic Implications

Vitiligo is an autoimmune skin disorder caused by dysfunctional pigment-producing melanocytes which are attacked by immune cells. Oxidative stress is considered to play a crucial role in activating consequent autoimmune responses related to vitiligo. Melanin synthesis by melanocytes is the main intracellular stressor, producing reactive oxygen species (ROS). Under normal physiological conditions, the antioxidative nuclear factor erythroid 2-related factor 2 (Nrf2) pathway functions as a crucial mediator for cells to resist oxidative stress. In pathological situations, such as with antioxidant defects or under inflammation, ROS accumulate and cause cell damage. Herein, we summarize events at the cellular level under excessive ROS in vitiligo and highlight exposure to melanocyte-specific antigens that trigger immune responses. Such responses lead to functional impairment and the death of melanocytes, which sequentially increase melanocyte cytotoxicity through both innate and adaptive immunity. This report provides new perspectives and advances our understanding of interrelationships between oxidative stress and autoimmunity in the pathogenesis of vitiligo. We describe progress with targeted antioxidant therapy, with the aim of providing potential therapeutic approaches.

Has the core outcome (domain) set for vitiligo been implemented? An updated systematic review on outcomes and outcome measures in vitiligo randomized clinical trials

BACKGROUND

In 2015, a major achievement in vitiligo research was the development of an internationally agreed upon core outcome domain set for randomized clinical trials (RCTs). Three outcomes were identified as being essential: repigmentation, side-effects/harms and maintenance of gained repigmentation. Four items were further recommended for inclusion. The following recommendations then followed: repigmentation should be assessed by measuring the percentage of repigmentation in quartiles (0-25%, 26-50%, 51-79%, 80-100%) and cosmetic acceptability of the results should be assessed using the Vitiligo Noticeability Scale.

OBJECTIVES

The primary objective of this study was to assess uptake of the core outcome domain set for RCTs in vitiligo. Secondary objectives were to update the systematic review on outcomes reported in vitiligo RCTs, and to assess whether repigmentation and cosmetic acceptability of the results were measured using the above-mentioned recommended scales.

METHODS

We searched PubMed, Cochrane Library (CENTRAL and Systematic Reviews) and ClinicalTrials.gov for vitiligo RCTs between November 2009 and March 2021. Screening and data extraction were independently performed on title and summary by two researchers. All outcomes and outcome measures reported in eligible RCTs were retrieved and collated.

RESULTS

In total, 174 RCTs were identified: 62 were published between 2009 and 2015, and 112 were published between 2016 and 2021.Thirty-eight different outcomes were reported. Repigmentation was the primary outcome in 89% of trials (150 of 169). Forty-nine different tools were used to measure repigmentation. Side-effects and harms were reported in 78% of trials (136 of 174). Maintenance of gained repigmentation was reported in only 11% of trials (20 of 174) and duration of follow-up varied greatly from 1 to 14 months. Cosmetic acceptability of the results and cessation of disease activity were assessed in only 2% of trials (four of 174). Quality of life of patients with vitiligo was assessed in 13% of trials (22 of 174). Finally, only 11 of 112 RCTs (10%) published between 2016 and 2021 reported all three essential core outcome domains (repigmentation, side-effects and maintenance of gained repigmentation) and none of the trials reported both essential and recommended core outcome domains.

CONCLUSIONS

Efforts are still needed to close the gap between set recommendations and RCT outcome reporting.

Regenerative Medicine-Based Treatment for Vitiligo: An Overview

Vitiligo is a complex disorder with an important effect on the self-esteem and social life of patients. It is the commonest acquired depigmentation disorder characterized by the development of white macules resulting from the selective loss of epidermal melanocytes. The pathophysiology is complex and involves genetic predisposition, environmental factors, oxidative stress, intrinsic metabolic dysfunctions, and abnormal inflammatory/immune responses. Although several therapeutic options have been proposed to stabilize the disease by stopping the depigmentation process and inducing durable repigmentation, no specific cure has yet been defined, and the long-term persistence of repigmentation is unpredictable. Recently, due to the progressive loss of functional melanocytes associated with failure to spontaneously recover pigmentation, several different cell-based and cell-free regenerative approaches have been suggested to treat vitiligo. This review gives an overview of clinical and preclinical evidence for innovative regenerative approaches for vitiligo patients.

Melanogenesis and Hypopigmentation: The Case of Vitiligo

Melanocytes are highly specialized dendritic cells that synthesize and store melanin in subcellular organelles called melanosomes, before transfer to keratinocytes. Melanin is a complex pigment that provides colour and photoprotection to the skin, hair and eyes. The process of synthesis of melanin is called melanogenesis and is regulated by various mechanisms and factors such as genetic, environmental and endocrine factors. The knowledge of the pigmentation process is important to understand hypopigmentation disorders such as vitiligo and also to design adequate treatments. In the present work, we review the signalling pathways involved in vitiligo. Finally, current therapies and treatments including topical, oral and phototherapies are discussed and described, emphasizing future therapies based on different pigmentation mechanisms.

Vitiligo: An Autoimmune Skin Disease and its Immunomodulatory Therapeutic Intervention

Vitiligo is a chronic autoimmune depigmenting skin disorder characterized by patches of the skin losing functional melanocytes. Multiple combinatorial factors are involved in disease development, among which immune T cells play a prominent role. The immune cells implicated in melanocyte destruction through adaptive immunity include CD8⁺ cytotoxic T cells and regulatory T cells, and aberrantly activated skin-resident memory T cells also play a role in melanocyte destruction. Over the past several years, major progress in understanding vitiligo pathogenesis has led to the development of targeted therapies. Janus kinase (JAK) inhibitors, which share the similar mechanism that autoactivates CD8⁺ T cells in chronic inflammatory diseases, have been reported to have therapeutic significance in vitiligo. Recently, immunomodulatory therapeutic interventions in vitiligo have been emerging. Mesenchymal stem cells (MSCs) regulate cytokine secretion and the balance of T-cell subsets, which makes them a promising cell-based treatment option for autoimmune diseases. The induction of MSC-mediated immunomodulation is complicated and occurs by contact-dependent mechanisms and soluble extracellular vesicle (EV) mediators. EVs released from MSCs contain various growth factors and cytokines with anti-inflammatory effects in the skin immune response. Here, we summarize and discuss the progress to date in targeted therapies that immunomodulate the niche environment of vitiligo, from the clinical trial of JAK inhibitors to the potential of MSCs and MSC-EVs. The available information was collected to highlight the need for further research into the treatment of vitiligo.

Surgical Interventions for Patients With Vitiligo: A Systematic Review and Meta-analysis

Importance

Surgical interventions are a key part of the therapeutic arsenal, especially in refractory and stable vitiligo. Comparison of treatment outcomes between the different surgical procedures and their respective adverse effects has not been adequately studied.

Objective

To investigate the reported treatment response following different surgical modalities in patients with vitiligo.

Data Sources

A comprehensive search of the MEDLINE, Embase, Web of Science, and Cochrane Library databases from the date of database inception to April 18, 2020, was conducted. The key search terms used were vitiligo, surgery, autologous, transplantation, punch, suction blister, and graft.

Study Selection

Of 1365 studies initially identified, the full texts of 358 articles were assessed for eligibility. A total of 117 studies were identified in which punch grafting (n = 19), thin skin grafting (n = 10), suction blister grafting (n = 29), noncultured epidermal cell suspension (n = 45), follicular cell suspension (n = 9), and cultured epidermal cell suspension (n = 17) were used.

Data Extraction and Synthesis

Three reviewers independently extracted data on study design, patients, intervention characteristics, and outcomes. Random effects meta-analyses using generic inverse-variance weighting were performed.

Main Outcomes and Measures

The primary outcomes were the rates of greater than 90%, 75%, and 50% repigmentation response. These rates were calculated by dividing the number of participants in an individual study who showed the corresponding repigmentation by the total number of participants who completed the study. The secondary outcomes were the factors associated with treatment response to the surgical intervention.

Results

Among the 117 unique studies and 8776 unique patients included in the analysis, rate of repigmentation of greater than 90% for surgical interventions was 52.69% (95% CI, 46.87%-58.50%) and 45.76% (95% CI, 30.67%-60.85%) for punch grafting, 72.08% (95% CI, 54.26%-89.89%) for thin skin grafting, 61.68% (95% CI, 47.44%-75.92%) for suction blister grafting, 47.51% (95% CI, 37.00%-58.03%) for noncultured epidermal cell suspension, 36.24% (95% CI, 18.92%-53.57%) for noncultured follicular cell suspension, and 56.82% (95% CI, 48.93%-64.71%) for cultured epidermal cell suspension. The rate of repigmentation of greater than 50% after any surgical intervention was 81.01% (95% CI, 78.18%-83.84%). In meta-regression analyses, the treatment response was associated with patient age (estimated slope, -1.1418), subtype of vitiligo (estimated slope, 0.3047), and anatomical sites (estimated slope, -0.4050).

Conclusions and Relevance

The findings of this systematic review and meta-analysis suggest that surgical intervention can be an effective option for refractory stable vitiligo. An appropriate procedure should be recommended based on patient age, site and size of the lesion, and costs.

Electrofulguration-assisted dermabrasion is comparable to manual dermabrasion in patients undergoing autologous non-cultured epidermal cell suspension for treatment of stable vitiligo: A randomized controlled trial

BACKGROUND

Recipient site preparation is a crucial step in non-cultured epidermal cell suspension (NCES) as it facilitates proper uptake of the grafted melanocytes.

OBJECTIVES

To compare the repigmentation rate of recipient sites prepared with manual dermabrasion (MD) versus electrofulguration-assisted dermabrasion (EF) in patients undergoing NCES for treatment of stable vitiligo.

METHODS

This was a prospective randomized study including 26 patients of stable vitiligo (VIDA 0 or -1), each having two patches of size greater than 3 × 3 cm located symmetrically or at the same site or a single patch of 6 × 6 cm or larger. After randomization of patches in the given patient, MD and EF were performed on recipient areas followed by NCES. The patients were followed up at 4 weekly intervals up to 24 weeks and assessed for extent of repigmentation and adverse effects if any.

RESULTS

Greater than 75% repigmentation was observed in 69.3% of the patches prepared by MD as compared to 73.1% patches prepared by EF at the end of 24 weeks (p = 0.791). The mean improvement in target VASI was 64.0% in the MD group as compared to 68.8% in the EF group (p = 0.21). Patches prepared by EF achieved successful repigmentation earlier as compared to patches prepared by MD (9.4 weeks vs 11.4 weeks, p = 0.12).

CONCLUSION

Both MD and EF have comparable outcomes with respect to all parameters.

Regenerative Medicine of Epithelia: Lessons From the Past and Future Goals

This article explores examples of successful and unsuccessful regenerative medicine on human epithelia. To evaluate the applications of the first regenerated tissues, the analysis of the past successes and failures addresses some pending issues and lay the groundwork for developing new therapies. Research should still be encouraged to fill the gap between pathologies, clinical applications and what regenerative medicine can attain with current knowledge.

Vitiligo: Translational research and effective therapeutic strategies

This is an exciting phase of vitiligo research with the current understanding of vitiligo pathogenesis and its translation to successful treatment. The pathogenetic origin of vitiligo revolves around autoimmunity with supporting role from many other factors like oxidative stress, inherent melanocyte defects, or defective keratinocytes and fibroblasts. Vitiligo can be classified into segmental or non-segmental depending upon the clinical presentation, or it can be classified as progressing or stable based on the activity of the disease. Vitiligo treatments need to be stratified depending upon which type of vitiligo we are treating and at which phase the vitiligo patient presents to us. There are two different aims of treatment of vitiligo. The first involves rescuing the melanocytes from the damage to arrest the depigmentation. The second strategy focuses on replenishing the melanocytes so that successful repigmentation is achieved. It is also important to maintain the disease in a stable phase or prevent relapse. As stability in non-segmental vitiligo is a dynamic process, maintenance of the stability of repigmentation is also an important consideration in the management of vitiligo. In this review, we shall briefly discuss the current options and future insight into the management of 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 (χ² P = 0.000 and χ² 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.

A prospective, randomized clinical study to compare the efficacy of recipient site preparation using dermabrasion, cryoblister, and dermaroller in autologous noncultured epidermal cell suspension in stable vitiligo

Noncultured epidermal cell suspension (NCES) is a well-established surgical treatment modality for stable vitiligo. The outcome of this procedure significantly depends on the method of recipient site preparation, a critical step to achieve cosmetically acceptable repigmentation. To compare the efficacy of recipient site preparation using three methods namely, dermabrasion, cryoblister, and dermaroller followed by NCES in stable vitiligo. In this single-center, prospective, intra-patient, randomized clinical trial; 36 participants having at least three vitiligo patches in same anatomic region with minimum lesional stability of 1 year were randomized 1:1:1 for recipient site preparation using manual dermabrasion, cryoblister, and dermaroller followed by NCES. Patients were followed up at 4, 8, and 12 weeks and assessment of extent and pattern of repigmentation, color match and patient satisfaction were done. Among 36 patients, 22 (61.1%) were females; mean (SD) age was 28.33 (9.4) years. Dermabrasion and cryoblister techniques showed equal efficacy with respect to extent of repigmentation (>75% repigmentation; 55.6% vs 47.2%; P = .63) and patient satisfaction score (20.2 ± 9.6 vs 19.9 ± 7.9, P = .194). However, dermabrasion was superior to cryoblister in terms of rapidity (65% vs 32.5% at 4 weeks, P = .04) and color match (47.2% vs 19.4%, P = .004). Dermaroller had poor repigmentation outcomes compared to both dermabrasion and cryoblister. Cryoblister as a method of recipient site preparation is equally effective as manual dermabrasion in NCES for attaining good to excellent repigmentation, but with risk of hyperpigmentation. However, dermaroller is inferior to both dermabrasion and cryoblister.

Surgical interventions for vitiligo

Since nonsurgical treatment of vitiligo is not always successful, surgical interventions are viable options for patients with refractory vitiligo. Surgical treatment is a method in which melanocytes of normal skin are transplanted into vitiligo lesions and provided as a repigmentation source. Such treatments are primarily divided into tissue grafting and cellular grafting, depending on the nature of the graft. Tissue grafting includes split-thickness skin grafting, suction blister grafting, punch grafting, hair follicle transplantation, and smashed-skin grafting. Cellular grafting includes non-cultured epidermal cell suspension transplantation, non-cultured follicular cell suspension transplantation, and cultured epidermal cell suspension transplantation. Among these, suction blister grafting and micro-punch grafting have been widely performed for localized refractory vitiligo, and non-cultured epidermal cell suspension transplantation is adopted as the standard treatment for extensive vitiligo. Research on cultured cellular grafting to treat larger vitiligo areas is also ongoing. Selecting patients with stable vitiligo that has not spread for over 12 months is the most critical factor in the surgical outcome. It is also important to choose an appropriate surgical modality for each patient, and a combination of various procedures often improves the overall outcome. In conclusion, surgical intervention can be an effective and safe option for patients with vitiligo refractory to conventional treatments. Non-cultured epidermal cell suspension transplantation, which was denied by New Health Technology Assessment in Korea, should be approved to benefit patients with refractory vitiligo.

Skin seeding technique with 0.5-mm micropunch grafting for vitiligo irrespective of the epidermal-dermal orientation: Animal and clinical studies

Micropunch grafting is the simplest surgical intervention for refractory vitiligo but is tedious and time-consuming. Therefore, we aimed to verify the efficacy and safety of dermal orientation grafting using motorized 0.5-mm micropunch grafting for vitiligo. In a preliminary animal study, 12-week-old rats were used to observe the healing process after the transplantation of dermal orientation grafts with various punch sizes. In a clinical trial, a total of 100 vitiligo patches in 50 patients with stable vitiligo were randomly allocated to motorized 0.5-mm micropunch grafting in epidermal and dermal orientations, respectively. The grafts were implanted at intervals of 5 mm at the recipient site. Treatment success was defined as greater than 75% repigmentation. In the animal study, all grafts were shown to be well integrated into the recipient site within 3 weeks. In the clinical trial, treatment success was achieved in 72% and 76% of the epidermal and dermal orientation groups, respectively; a cobblestone appearance was observed in 4% and 2%, respectively. In conclusion, we demonstrated that this new grafting method irrespective of epidermal-dermal orientation using motorized 0.5-mm micropunch grafting was effective and safe. We have named this the "skin seeding technique" and it differs from traditional punch grafting in that it can be performed regardless of the graft orientation.