Coverage of Large Pediatric Wounds With Cultured Epithelial Autografts in Congenital Nevi and Burns: Results and Technique:

A clinical and biologic review of congenital melanocytic nevi

Congenital melanocytic nevi (CMN) are the result of aberrations in the mitogen-activated protein kinase signal transduction pathway caused by postzygotic somatic mutations. The estimated incidence of newborns with CMN is 1%-2%. The main complications of CMN include proliferative nodules, melanomas, and neurocutaneous melanosis, and the latter two are the most troublesome issues to address. Treatments are primarily taken into account for aesthetic purposes and the reduction of melanoma risk. Due to the much lower incidence of malignant transformation observed in recent studies than in previous data, clinical management paradigms for CMN patients have gradually shifted towards conservative observation and close monitoring. Surgery and lasers are still the main treatments, and targeted therapy may be a promising strategy to help manage complications. With the increase in awareness of mental health, increasing focus has been placed on the quality of life (QoL) and psychological issues of both CMN patients and their parents. Recent studies have revealed that families coping with CMN might endure intense pressure, a major loss in QoL, and psychological problems after diagnosis and during treatment. Here, we sought to present an overview of genetic basis, complications, treatments, and psychological issues related to CMN and hope to provide better management for patients with CMN.

Challenges in the management of extensive aplasia cutis congenita

Aplasia cutis congenita (ACC) is a rare group of congenital disorders characterised by focal or widespread absence of skin, predominantly affecting the scalp. A Malay female infant was born at 37 weeks with extensive ACC, affecting 37% of total body surface area, including her scalp and trunk. There is no consensus on the management of ACC given the rarity and variable presentation. A multi-disciplinary team comprising neonatologists, paediatric dermatologists, plastic surgeons and medical laboratory scientists at the skin bank, employed a more aggressive surgical approach with the aim of avoiding potentially catastrophic morbidity, including sagittal sinus haemorrhage and brain herniation. Out of several surgical options, the team used a staged artificial dermal matrix (Integra) and cultured epithelial autograft application, followed by regular wound dressing, and eventually allowed the child to achieve complete epithelialisation of her trunk, and most of scalp before she was discharged from hospital.

Treatment of giant congenital melanocytic nevi with cultured epithelial autografts: Clinical and histopathological analysis

Introduction

Curettage and dermabrasion are effective in the treatment of giant congenital melanocytic nevi (GCMN); however, local infection and hypertrophic scar formation are major issues. Thus, we applied cultured epithelial autografts (CEA) on skin defects after curettage or abrasion of GCMN and assessed the postoperative outcomes.

Methods

Seven nevi lesions of five patients (aged 3 months to 24 years) were treated with CEA after curettage or abrasion with a dermatome or a surgical bar, respectively. We assessed the postoperative outcomes, including CEA take ratio, erosion and/or ulcer formation in the acute phase, hospitalization days, Vancouver scar scale, and color improvement one year after the operation. In addition, a histological evaluation of a skin biopsy was performed over one year after the operation.

Results

The CEAs took well on the wound, and the wound surface was mostly epithelized by postoperative day 7 in all cases. While hypertrophic scar formation and slight pigmentation were observed in some lesions, the color was improved in all of the treated lesions. Histopathological examination revealed that the regenerated epidermis had stratified keratinocytes with rete ridges, and the dermal layer without nevus cells regenerated above the remaining dermis layer.

Conclusions

In this study, we found that early epithelialization and regeneration of the dermal layer was achieved after the application of CEA, suggesting that CEA could be an effective option after curettage or abrasion of GCMN.

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Cultured epithelial autograft (CEA) application is effective in the treatment of giant congenital melanocytic nevi.

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The grafted CEA takes well on skin defects post curettage and abrasion.

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CEAs can achieve rapid epithelization.

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Normal dermal tissue regenerates after CEA application.

Using Various Skin Graft Techniques in Major Burn Reconstruction: A Lesson Learned From a Taiwanese Cornstarch Explosion

PURPOSE

Four hundred and ninety-nine patients had burn injuries in an explosion in Taiwan on June 27, 2015, 24 were admitted to the intensive care units of Taipei Veterans General Hospital. This study details our experience with surgical management of these patients, focusing primarily on various skin graft techniques.

MATERIALS AND METHODS

This single-center retrospective study included patients who underwent at least one of the previously mentioned skin graft techniques because of extensive skin defects. The demography, burn diagram, treatment modalities, postoperative outcome, and costs were all analyzed, and a comparison with traditional mesh skin grafts was performed. The literature was also reviewed.

RESULTS

Fourteen patients underwent the Meek skin graft technique. Only 3 received ReCell and 1 cultured epithelial autograft (CEA) at separate time point. Overall, the autologous skin grafts, including Meek/ReCell/CEA were completed within 6 months. The average skin graft success rate was approximately 72.9%, 79.2%, and 38% in Meek, ReCell, and CEA, respectively. The infection rate was approximately 35.7%, 25%, and 100% in Meek, ReCell, and CEA, respectively. The average surgical cost and total medical cost were significantly higher in patients who underwent Meek/ReCell/CEA treatments.

CONCLUSIONS

In our experience, Meek and ReCell treatments had acceptable success rates, but CEA treatment not. ReCell and CEA treatments are useful in the event of extremely limited donor sites, and they are fragile, easily infected, and technically challenging. These techniques also require longer hospitalization and tend to be more expensive, all factors that should be considered when assessing treatment options.

Effect of Mature Adipocyte-Derived Dedifferentiated Fat Cells on Formation of Basement Membrane after Cultured Epithelial Autograft on Artificial Dermis

BACKGROUND

Artificial dermis is an important option for preparing full-thickness wounds for cultured epithelial autografting. Long-term fragility after cultured epithelial autografting remains a problem, probably because of the lack of basement membrane proteins. The authors hypothesized that treating artificial dermis with mesenchymal stem cells would promote basement membrane protein production. The authors tested this using dedifferentiated fat cells in a porcine experimental model.

METHODS

This study used four male crossbred (Landrace, Large White, and Duroc) swine. Cultured epithelium and dedifferentiated fat cells were prepared from skin and subcutaneous fat tissue harvested from the cervical region. Full-thickness open dorsal wounds were created and treated with artificial dermis to prepare a graft bed for cultured epithelial autograft. Two groups were established: the control group (artificial dermis treated with 0.5 ml of normal saline solution applied to the wounds) and the dedifferentiated fat group (artificial dermis treated with 0.5 × 10 dedifferentiated fat cells suspended in 0.5 ml of normal saline solution sprayed onto the wounds). On postoperative day 10, the prepared cultured epithelium was grafted onto the generated dermis-like tissue. Fourteen days later, tissue specimens were harvested and evaluated histologically.

RESULTS

Light microscopy of hematoxylin and eosin-stained sections revealed the beginning of rete ridge formation in the dedifferentiated fat group. Synthesis of both collagen IV and laminin-5 was significantly enhanced in the dedifferentiated fat group. Transmission electron microscopy revealed a nearly mature basement membrane, including anchoring fibrils in the dedifferentiated fat group.

CONCLUSION

Combined use of artificial dermis and dedifferentiated fat cells promotes post-cultured epithelial autograft production and deposition of basement membrane proteins at the dermal-epidermal junction and basement membrane development, including anchoring fibrils.

Cell therapy for severe burn wound healing

Cell therapy has emerged as an important component of life-saving procedures in treating burns. Over past decades, advances in stem cells and regenerative medicine have offered exciting opportunities of developing cell-based alternatives and demonstrated the potential and feasibility of various stem cells for burn wound healing. However, there are still scientific and technical issues that should be resolved to facilitate the full potential of the cellular devices. More evidence from large, randomly controlled trials is also needed to understand the clinical impact of cell therapy in burns. This article aims to provide an up-to-date review of the research development and clinical applications of cell therapies in burn wound healing and skin regeneration.

An adipogenic gel for surgical reconstruction of the subcutaneous fat layer in a rat model

'Off-the-shelf' tissue-engineered skin alternatives for epidermal and dermal skin layers are available; however, no such alternative for the subdermal fat layer exists. Without this well-vascularized layer, skin graft take is variable and grafts may have reduced mobility, contracture and contour defects. In this study a novel adipose-derived acellular matrix (Adipogel) was investigated for its properties to generate subdermal fat in a rat model. In a dorsal thoracic site, a 1 × 1 cm Adipogel implant was inserted within a subdermal fat layer defect. In a dorsal lumbar site, an Adipogel implant was inserted in a subfascial pocket. Contralateral control defects remained empty. At 8 weeks wound/implant sites were evaluated histologically, immunohistochemically and morphometrically. Identifiable thoracic Adipogel implants lost volume in vivo over 8 weeks. Neovascularization and adipogenesis were evident within implants and adipocyte percentage volume was 33.07 ± 6.55% (mean ± SEM). A comparison of entire cross-sections of thoracic wounds demonstrated a significant increase in total wound fat in Adipogel-implanted wounds (37.19 ± 4.48%, mean ± SEM) compared to control (16.53 ± 4.60%; p = 0.0092), indicating that some Adipogel had been completely converted to normal fat. At the lumbar site, Adipogel also lost volume, appearing flattened, although fat generation and angiogenesis occurred. At both sites macrophage infiltration was mild, whilst many infiltrating cells were PDGFRβ-positive mesenchymal cells. Adipogel is adipogenic and angiogenic and is a promising candidate for subcutaneous fat regeneration; it has the potential to be a valuable adjunct to wound-healing therapy and reconstructive surgery practice. Copyright © 2015 John Wiley & Sons, Ltd.

Changes in the Dermal Structure during Cultured Epidermal Autograft Engraftment Process

The use of cultured epithelial autografts for the treatment of extensive burn wounds has become popular in recent years. We examined extensive burn wounds in 14 patients by using a combination of autograft and cultured epithelial autografts developed in Japan (JACE).

Application of the cultured epidermal autograft "JACE(®") for treatment of severe burns: Results of a 6-year multicenter surveillance in Japan

BACKGROUND

In the 1970s, Green et al. developed a method that involved culturing keratinocyte sheets and used for treatment of burns. Since then, the take rate of cultured epidermal autograft (CEA) onto fascia, granulation tissue, or allografts has been extensively reported, while that on an artificial dermis in a large case series is not. Moreover, the contribution of CEA to patient survival has not been analyzed in a multicenter study.

METHODS

We conducted a 6-year multicenter surveillance on the application of the CEA "JACE(®") for treatment of burns >30% total body surface area (TBSA) across 118 Japanese hospitals. This surveillance included 216 patients and 718 graft sites for efficacy analysis. The CEA take rate at 4 weeks after grafting was evaluated, and safety was monitored until 52 weeks. In addition, the survival curve obtained in this study and the data obtained from the Tokyo Burn Unit Association (TBUA) were compared.

RESULTS

The mean CEA take rates at week 4 were 66% (sites) and 68% (patients), and the rate on the artificial dermis was 65% for 226 sites. CEA application combined with wide split-thickness auto or patch autograft increased the CEA take rate. On comparison with the data obtained from the TBUA, which included data on individuals with burns of the same severity, CEA application was found to contribute to patient survival until 7 weeks after burn.

CONCLUSIONS

We reported the take rate of CEA based on a 6-year multicenter surveillance. From our results, we found that the application of CEA is a useful treatment for the patients with extensive burns.

First experience using cultured epidermal autografts in Taiwan for burn victims of the Formosa Fun Coast Water Park explosion, as part of Japanese medical assistance

On June 27, 2015, a flammable starch-based powder exploded at Formosa Fun Coast in Taipei, Taiwan, injuring 499 people, and more than 200 people were in critical condition with severe burns. Although a cultured epidermal autograft (CEA) was not approved or used in clinical practice, the Taiwan Food and Drug Administration requested a Japanese CEA manufacturer to donate CEA for the burn victims as part of international medical assistance. The authors cooperated in this project and participated in the patient selection, wound bed management for CEA, and technical assistance for CEA use. Here, we provide an overview of the project. Nine patients were enrolled, and two patients were excluded from the skin biopsy; seven skin biopsies were collected approximately 1 month after the disaster. The average TBSA% burned was 81.0%, and the mean age was 20.1 years. CEA was grafted in five patients; wound closure had been obtained in one patient, and one patient was severely ill at the time of grafting. The CEA was combined with a wide split auto mesh graft or patch graft. The mean re-epithelization rate at 4 weeks after the grafting was 84.2% by patient, and all of the patients survived. Although this project had many obstacles to overcome, CEA grafting was successful and contributed to wound closure and survival.

Experience of using cultured epithelial autografts for the extensive burn wounds in eight patients

In Japan, the cultured epithelial autografts "JACE" was accepted as a health insurance adaptation from January 1, 2009. We examined the extensive burn wounds in 8 patients by using a combination of autograft and JACE. After debridement, we managed the wound bed preparation by using artificial dermis. The wound bed was covered with fine tissue 2 weeks after we implanted artificial dermis and trafermin was used every day. Meshed 6:1 split-thickness autografts were placed onto the recipient wound bed under the JACE. The epidermalization was nearly complete within 3 to 4 weeks.

RESULTS

A total of 39 patients underwent medical treatment of burns. All patients burned more than 30% total body surface area (TBSA). We divided them into 2 groups. The control group consisted of 31 patient, 23 men and 8 women. They underwent operation not using JACE but only autograft. The average age of the patients was 59.61 (3.85) years. The TBSA burned in this control group was 58.94% (3.89%). Operation times were 2.16 (0.24) hours. The overall survival rate was 35.5%. The study group consisted of 8 patients, 5 men and 3 women. The average age of the patients was 56.38 (7.04) years. The TBSA burned in this study group was 51.63% (4.17%). Operation times were 4.25 (0.59) hours, and the overall survival rate in this study group was 87.5%. The average take rate of JACE was 80.0% (3.09%) 4 weeks postoperatively.

CONCLUSIONS

JACE is one of the cultured epithelial autografts. Although we managed the wound bed preparation by using artificial dermis instead of cryopreserved cadaver allograft, we were able to recognize a good result from grafting JACE on meshed 6:1 split-thickness autografts. The study group observed a significant difference in operation times compared with the control group. However, this treatment contributed to reducing the area of the donor site.

Capturing epidermal stemness for regenerative medicine

The skin is privileged because several skin-derived stem cells (epithelial stem cells from epidermis and its appendages, mesenchymal stem cells from dermis and subcutis, melanocyte stem cells) can be efficiently captured for therapeutic use. Main indications remain the permanent coverage of extensive third degree burns and healing of chronic cutaneous wounds, but recent advances in gene therapy technology open the door to the treatment of disabling inherited skin diseases with genetically corrected keratinocyte stem cells. Therapeutic skin stem cells that were initially cultured in research or hospital laboratories must be produced according strict regulatory guidelines, which ensure patients and medical teams that the medicinal cell products are safe, of constant quality and manufactured according to state-of-the art technology. Nonetheless, it does not warrant clinical efficacy and permanent engraftment of autologous stem cells remains variable. There are many challenges ahead to improve efficacy among which to keep telomere-dependent senescence and telomere-independent senescence (clonal conversion) to a minimum in cell culture and to understand the cellular and molecular mechanisms implicated in engraftment. Finally, medicinal stem cells are expansive to produce and reimbursement of costs by health insurances is a major concern in many countries.

Regenerative medicine as applied to general surgery

The present review illustrates the state of the art of regenerative medicine (RM) as applied to surgical diseases and demonstrates that this field has the potential to address some of the unmet needs in surgery. RM is a multidisciplinary field whose purpose is to regenerate in vivo or ex vivo human cells, tissues, or organs to restore or establish normal function through exploitation of the potential to regenerate, which is intrinsic to human cells, tissues, and organs. RM uses cells and/or specially designed biomaterials to reach its goals and RM-based therapies are already in use in several clinical trials in most fields of surgery. The main challenges for investigators are threefold: Creation of an appropriate microenvironment ex vivo that is able to sustain cell physiology and function in order to generate the desired cells or body parts; identification and appropriate manipulation of cells that have the potential to generate parenchymal, stromal and vascular components on demand, both in vivo and ex vivo; and production of smart materials that are able to drive cell fate.

Review of burn injury research for the year 2009

Research in burn care for the calendar year 2009 was robust and diverse with >1400 research articles published on a wide range of topics. In this review, the authors highlight some innovative and potentially impactful research related to the overall care of burn- injured patients. The authors grouped articles according to the following categories: critical care, infection, inhalation injury, epidemiology, psychology, wound characterization and treatment, nutrition and metabolism, pain and itch management, burn reconstruction, and rehabilitation. They found that the holistic nature of burn care is reflected in the diverse research performed in 2009 throughout the world and that this research has provided important evidence that has improved or will improve burn care overall.