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Human cultured gingival epithelial sheets were used as an autologous grafting material for regenerating gingival tissue in the maxillary left and mandibular right quadrants of a patient with chronic desquamative gingivitis. Six months post-surgery in both treated areas, there were gains in keratinized gingiva and no signs of gingival inflammation compared to presurgery. In the maxillary left quadrant, preoperative histopathologic findings revealed the epithelium was separated from the connective tissue and inflammatory cells were extensive. After grafting with the gingival epithelial sheets, inflammatory cells were decreased and separation between epithelium and connective tissue was not observed. The human cultured gingival epithelial sheets fabricated using tissue engineering technology showed significant promise for gingival augmentation in periodontal therapy. [ABSTRACT FROM AUTHOR]

Abstract: Background: Acquired skin hypopigmentation has many etiologies, including autoimmune melanocyte destruction, skin aging, inflammation, and chemical exposure. Distinguishing lesions from normally pigmented skin is clinically important to precisely assess disease severity. However, no gold standard assessment method has been reported. We aimed to investigate whether spectrophotometers are useful for assessing vitiligo and rhododendrol (4‐(4‐hydroxyphenol)‐2‐butanol) (Rhododenol®)‐induced leukoderma disease severity by quantifying skin color. Methods: Mexameter® MX18 and CM‐700d spectrophotometer were used for assessing vitiligo/leukoderma by measuring melanin index, L*a*b* color space, and ΔE*ab value, which represents the color difference between two subjects and is calculated by the values of L*a*b*. Results: MX18 and CM‐700d can quantitatively distinguish vitiligo/leukoderma from normally pigmented skin based on melanin index. CM‐700d consistently quantified the color of vitiligo/leukoderma lesions and surrounding normally pigmented skin in L*a*b* color spaces and ΔE*ab. ΔE*ab is well correlated with melanin index and clinical appearance. Conclusion: ΔE*ab has been frequently used in aesthetic dentistry; however, current study is the first to use it in the measurement of skin color. ΔE*ab seems to be a useful parameter to evaluate the color contrast between vitiligo/leukoderma and surrounding normally pigmented skin and can be used to evaluate disease severity and patient's quality of life. [ABSTRACT FROM AUTHOR]

Background: No efficient treatment has yet been established for epidermolytic ichthyosis (EI), which is caused by pathogenic variants of KRT1 or KRT10. Patients with ichthyosis with confetti (IWC) have multiple normal-appearing spots, caused by the revertant somatic recombination of pathogenic variants that occurs at each spot independently. Additionally, some patients with EI have large areas of normal skin due to revertant postzygotic mosaicism., Objectives: To assess the feasibility of transplanting cultured epidermal autografts (CEAs) produced from revertant epidermal keratinocytes in patients with EI and IWC., Methods: We performed a clinical trial of treatment with CEAs produced from each patient's own revertant epidermal keratinocytes as a proof-of-concept study. This was a single-arm, open, unmasked, uncontrolled, single-assignment, treatment-purpose study. The primary outcome was the percentage area that lacked recurrence of ichthyosis lesions 4 weeks after the final transplant. The secondary outcome was the percentage area lacking recurrence of ichthyosis lesions 24 weeks after the initial transplantation. The trial was registered with the Japan Registry of Clinical Trials (jRCTb041190097)., Results: We successfully produced CEAs from genetically confirmed revertant skin from two patients with mosaic EI and from one patient with IWC and confirmed by amplicon sequencing and droplet digital polymerase chain reaction analysis that the CEAs mainly consisted of revertant wild-type cells. Single-cell RNA sequencing analysis confirmed the normal proliferation and safety profiling of CEAs. CEAs were transplanted onto desquamated lesional sites in the patients. Four weeks post-transplantation, the percentage area lacking recurrence of ichthyosis lesions in the three patients was 40%, 100% and 100% respectively, although recurrence of ichthyosis lesions was seen at the site of CEA transplantation in all three patients at 24 weeks post-transplantation., Conclusions: CEAs from normal skin have the potential to be a safe and local treatment option for EI and IWC., Competing Interests: Conflicts of interest The authors declare no conflicts of interest., (© The Author(s) 2024. Published by Oxford University Press on behalf of British Association of Dermatologists.)

Porokeratosis is a clonal keratinization disorder characterized by solitary, linearly arranged, or generally distributed multiple skin lesions. Previous studies showed that genetic alterations in MVK, PMVK, MVD, or FDPS-genes in the mevalonate pathway-cause hereditary porokeratosis, with skin lesions harboring germline and lesion-specific somatic variants on opposite alleles. Here, we identified non-hereditary porokeratosis associated with epigenetic silencing of FDFT1, another gene in the mevalonate pathway. Skin lesions of the generalized form had germline and lesion-specific somatic variants on opposite alleles in FDFT1, representing FDFT1-associated hereditary porokeratosis identified in this study. Conversely, lesions of the solitary or linearly arranged localized form had somatic bi-allelic promoter hypermethylation or mono-allelic promoter hypermethylation with somatic genetic alterations on opposite alleles in FDFT1, indicating non-hereditary porokeratosis. FDFT1 localization was uniformly diminished within the lesions, and lesion-derived keratinocytes showed cholesterol dependence for cell growth and altered expression of genes related to cell-cycle and epidermal development, confirming that lesions form by clonal expansion of FDFT1-deficient keratinocytes. In some individuals with the localized form, gene-specific promoter hypermethylation of FDFT1 was detected in morphologically normal epidermis adjacent to methylation-related lesions but not distal to these lesions, suggesting that asymptomatic somatic epigenetic mosaicism of FDFT1 predisposes certain skin areas to the disease. Finally, consistent with its genetic etiology, topical statin treatment ameliorated lesions in FDFT1-deficient porokeratosis. In conclusion, we identified bi-allelic genetic and/or epigenetic alterations of FDFT1 as a cause of porokeratosis and shed light on the pathogenesis of skin mosaicism involving clonal expansion of epigenetically altered cells., Competing Interests: Declaration of interests T.T. and M.I. are employees of Japan Tissue Engineering Co., Ltd., (Copyright © 2024 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.)

Japan Tissue Engineering Co., Ltd., J-TEC, was launched in 1999 to industrialize regenerative medicine in Japan. We developed the first regenerative medicine product, JACE (autologous cultured epidermis), which received PMDA approval for treating serious burns in 2007. Then, JACC (autologous cultured cartilage), the second product, was approved in 2012 for efficacy on traumatic cartilage defects. In 2014, the Pharmaceutical Affairs Law was revised to the Pharmaceutical and Medical Device Act, and regenerative medicine products, including gene therapies, were newly classified to accelerate productization. Subsequently, Nepic (autologous cultured corneal epithelium) and Ocural (autologous cultured oral mucosal epithelium) for epithelialization of limbal stem cell deficiencies in ophthalmology were approved in 2020 and 2021, respectively. Furthermore, a new product, JACEMIN (autologous cultured epidermis maintaining melanocyte) for vitiligo treatment was approved in 2023. We have developed five products of regenerative medicine that construct human tissues to graft rather than injectable cell suspensions like drugs. To develop regenerative medicine products, it is necessary to ensure the safety of raw materials, standardize the cultivation process, examine cell characteristics on GLP tests, construct transportation methods, build GCTP facilities, and conduct clinical trials on GCP. Re-examinations of JACE for serious burns and JACC for cartilage defects were completed after 7 years of all-case postmarketing surveillance. The commercialization of these products has become a benchmark for domestic regulation and has induced the development of a regenerative medicine industry promoted by Japan.

Changes in cell fluidity have been observed in various cellular tissues and are strongly linked to biological phenomena such as self-organization. Recent studies suggested variety of mechanisms and factors, which are still being investigated. This study aimed to investigate changes in cell fluidity in multi-layered cell sheets, by exploring the collective arrest of cell motion and its release in cultures of corneal epithelial cells. We constructed mathematical models to simulate the behaviors of individual cells, including cell differentiation and time-dependent changes in cell-cell connections, which are defined by stochastic or kinetic rules. Changes in cell fluidity and cell sheet structures were expressed by simulating autonomous cell behaviors and interactions in tissues using an agent-based model. A single-cell level spatiotemporal analysis of cell state transition between migratable and non-migratable states revealed that the release from collective arrest of cell motion was initially triggered by a decreased ability to form cell-cell connections in the suprabasal layers, and was propagated by chain migration. Notably, the disruption of cell-cell connections and stratification occurred in the region of migratable state cells. Hence, a modeling approach that considers time-dependent changes in cell properties and behavior, and spatiotemporal analysis at the single-cell level can effectively delineate emergent phenomena arising from the complex interplay of cells., (Copyright © 2023 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Background: Autologous cultured epidermis (CE) is successfully used in burn care, but it requires a manufacturing time of three weeks and is very expensive owing to its custom-made nature of treatment. To compensate this disadvantage, dried allogeneic CE promises a novel therapeutic approach; and previous reports have demonstrated its efficacy in promoting wound healing using a murine skin defect model. Herein, a prospective clinical study was conducted to confirm the safety and efficacy of dried allogeneic CE for wound treatment., Methods: Dried CE was manufactured using donor keratinocytes obtained from excess surgical skin and applied to skin defects that were at least 3 cm in length and less than 10 % of the body surface area of the patients. The patients were observed for 14 days after CE application. The primary endpoint was the incidence of adverse events and the secondary endpoint was the percentage of wound healed since baseline, on days 7 and 14. Furthermore, as a stratified analysis, the percentage of wound healed, specified as deep dermal burns, was calculated., Results: Six patients (five burns and one skin ulcer after necrotizing fasciitis) enrolled in the study. As a serious adverse event, a local infection was observed in one patient, which resolved by debridement and conventional skin grafting. Other adverse events that were potentially related to this treatment included two cases of skin erosion, and one case of systemic fever. No unresolved adverse events remained at the end of the study period. The percentage of wound healed was 73.4 ± 19.2 % on Day 7, and 92.2 ± 11.8 % on Day 14. When the targeted disease was restricted to deep dermal burns, the percentage of wound healed was 69.9 ± 28.9 % on Day 7 and 90.5 ± 13.2 % on Day 14., Conclusion: Treatment with dried CE was safely performed without any unresolved severe adverse effects. Dried CE is a new and promising modality for skin defect treatment, such as burns and ulcers, and is expected to compensate for the disadvantages of autologous CE. However, large-scale clinical trials are required to confirm their efficacy., Competing Interests: Competing interests J-TEC supported to manufacture cultured epidermis used in this study. Y.S. and M.I. were employed by J-TEC and the funder provided support in the form of salaries for Y.S., Y.N. and M.I. but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The other authors do not have any competing interest to declare., (Copyright © 2022 Elsevier Ltd and International Society of Burns Injuries. All rights reserved.)

Purpose: To confirm the efficacy and safety of Good Manufacturing Practice (GMP)-compliant autologous cultivated limbal epithelial cell sheets in government-controlled clinical trials that adhered to Good Clinical Practice stipulations for patients with unilateral limbal stem cell deficiency (LSCD)., Design: A prospective, multicenter, open-label, uncontrolled, single-arm clinical trial., Participants: Ten consecutive eyes of 10 patients with unilateral LSCD were followed for 2 years after surgery. Preoperative LSCD stage was IIB in 4 eyes and III in 6 eyes., Methods: A limbal tissue biopsy was obtained from the healthy eye, after which limbal stem cells were dissociated and cultivated on temperature-responsive culture surfaces. All cell sheets were fabricated in a GMP-grade facility under established standard operating procedures. Cell sheets were evaluated using defined shipment criteria before transplantation, and only those that met the criteria were used. The cell sheet was transplanted onto each of the patients' diseased eye after removing the conjunctival scar tissue that covered the corneal surface. The severity of LSCD was determined according to a staging method agreed on by global consensus, with eyes evaluated as being in stages IA-C representing successful corneal epithelial reconstruction. Diagnosis and staging of LSCD were determined by the trial's Eligibility Judgment Committee and Effect Assessment Committee using slit-lamp photographs including fluorescein staining. Both committees comprised 2 or 3 third-party cornea specialists, who were provided with information anonymously and randomly., Main Outcome Measure: Corneal epithelial reconstruction rate was the primary end point., Results: Corneal epithelial reconstruction was successful in 6 of 10 eyes (60%) 1 year postoperatively and was significantly higher than the 15% clinically significant efficacy rate achieved by allogeneic limbal transplantation. The reconstruction rate was 70% of eyes 2 years postoperatively. Additionally, improvements in visual acuity were noted in 50% and 60% of eyes at 1 and 2 years, respectively. No clinically significant transplantation-related adverse events were observed., Conclusions: The efficacy and safety of cultivated limbal epithelial cell sheet transplantation were thus confirmed, and the cell sheet, named "Nepic," is now approved as a cellular and tissue-based product in Japan., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references., (Copyright © 2023. Published by Elsevier Inc.)

Regenerative medicine products using allogeneic cells, such as allogeneic cultured epidermis (allo-CE), have become a more critical therapeutic method for the treatment of burns. However, there are no clinically available allo-CE products in Japan. Therefore, establishing a quality-controlled cell bank is mandatory to create regenerative medical products using allogeneic cells. In this study, we selected ten patients from the Department of Plastic Surgery of Kyoto University Hospital to become cell donors. We performed medical interviews and blood sampling for the donor to ensure virus safety. We examined the tissues and isolated cells by performing a nucleic acid test (NAT). To establish a master cell bank, quality evaluation was performed according to the International Conference of Harmonization (ICH) Q5A. Serological tests of the blood samples from the ten donors showed that two of them were ineligible. The cells registered in the cell bank were found to be compatible after virus testing was performed, and a master cell bank was constructed. Hence, we established a keratinocyte and fibroblast bank of clinically usable human cultured cells in Japan for the first time., (© 2022. The Japanese Society for Artificial Organs.)

Introduction: Autologous cultured epidermis (CE) is an effective approach for overcoming the deficiency of donor sites to treat extensive burns. However, the production of autologous CE takes 3-4 weeks, which prevents its use during the life-threatening period of severe burns. In contrast, allogeneic CE can be prepared in advance and used as a wound dressing, releasing several growth factors stimulating the activity of recipient cells at the application site. Dried CE is prepared by drying CEs under controlled temperature and humidity conditions until all the water is completely removed and no viable cells are present. Dried CE accelerates wound healing in a murine skin defect model and is potentially a new therapeutic strategy. However, the dried CE safety and efficacy have not yet been studied in large animal models. Therefore, we studied the safety and efficacy of human-dried CE in wound healing using a miniature swine model., Methods: Human CE was manufactured using Green's method from donor keratinocytes. Three types of CEs (Fresh, Cryopreserved, and Dried) were prepared, and the ability of each CE to promote keratinocyte proliferation was confirmed in vitro . Extracts of the three CEs were added to keratinocytes seeded in 12-well plates, and cell proliferation was evaluated using the WST-8 assay for 7 days. Next, we prepared a partial-thickness skin defect on the back of a miniature swine and applied three types of human CE to evaluate wound healing promotion. On days 4 and 7, the specimens were harvested for hematoxylin-eosin, AZAN, and anti-CD31 staining to assess epithelialization, granulation tissue, and capillary formation., Results: The conditioned medium containing dried CE extract significantly enhanced keratinocyte proliferation compared to the control group ( P  < 0.05). In vivo experiments revealed that human-dried CE significantly accelerated epithelialization at day 7 to the same extent as fresh CE, compared to the control group ( P  < 0.05). The three CE groups similarly affected granulation formation and neovascularization., Conclusions: Dried CE accelerated epithelialization in a porcine partial-thickness skin defect model, suggesting that it may be an effective burn treatment alternative. A clinical study with a long-term follow-up is needed to assess the applicability of CEs in clinics., Competing Interests: Japan Tissue Engineering, Co., Ltd. (J-TEC) supported the manufacturing of the cultured epidermis used in this study. Y.S. and M.I. were employed by J-TEC, and the funder provided support in the form of salaries for Y.S. and M.I. but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The other authors declare no competing interests., (© 2023 The Japanese Society for Regenerative Medicine. Production and hosting by Elsevier B.V.)

Cryopreserved allogeneic cultured epidermis (CE) is used for treating second-degree burn wounds and diabetic foot ulcers; however, the need for cryopreservation limits its use. We have previously reported that CE accelerates wound healing irrespective of its viability and hypothesized that dehydrated CEs lacking living cells may act as an effective wound dressing. We prepared dried CE and investigated its morphological and physical properties and wound-healing effects and compared them with those of cryopreserved CE. Hematoxylin-eosin staining, immunostaining for basement membrane, and electron microscopy revealed that the morphologies of dried CE and cryopreserved CE were comparable and that the membrane structure was not damaged. The breaking strength, modulus of elasticity, and water permeability of dried CE were comparable with those of the cryopreserved CE. Furthermore, the levels of various active cytokines and chemokines in dried CE were comparable with those in cryopreserved CE. Dried CE applied to skin defect in diabetic mice significantly reduced the wound area and increased the new epithelium length 4 and 7 days after implantation, similar to that observed for cryopreserved CE. Consequently, dried CE had similar morphological and physical properties and wound-healing effects compared with those of cryopreserved CE and can be a physiological and versatile wound-dressing., (© 2022. The Author(s).)

Cultured epidermal autografts (CEA) are surgical therapeutic alternatives for patients with stable vitiligo resistant to conventional medical treatments. In the present study, we assessed color matching before and at 12 months after CEA treatment. Eleven patients with 16 vitiligo lesions were included in this prospective study. The recipient sites were prepared by CO 2 laser superficial ablation and subjected to CEA application. We clinically evaluated and categorized the color matching of the repigmented skin as well as the percentage of repigmentation. We also obtained three color values (L*a*b*) for the vitiligo lesions and surrounding normally pigmented skin. We then calculated the color differences between the two regions and compared them before and at 12 months after treatment. The mean percentage of repigmentation was 63.3% at 12 months. Six of the 16 lesions were categorized as "same as" and had color difference values of ≤5 at 12 months after treatment. Clinical evaluation of the color matching coincided well with the calculated color difference values. CEA application after CO 2 laser superficial ablation was useful for treating vitiligo assessed by the percentage of repigmentation and color matching. Quantification of color differences may be a useful parameter for evaluating color matching in vitiligo., (© 2021 The Authors. The Journal of Dermatology published by John Wiley & Sons Australia, Ltd on behalf of Japanese Dermatological Association.)

Allogeneic cultured epidermis (allo-CE) is a cultured keratinocyte sheet manufactured from donor cells and promotes wound healing when used in deep dermal burns, donor sites, and chronic ulcers and serves as a wound dressing. Allo-CE is usually cryopreserved to be ready to use. However, the cryopreservation procedure will damage the cell viability, and the influence of Allo-CE, according to its viability or wound healing process, has not been evaluated sufficiently. In this study, we aimed to prove the influence of keratinocyte viability contained in allo-CEs on wound healing. We prepared CEs with Green's method using keratinocytes obtained from a polydactyly patient and then prepared four kinds of CEs with different cell viabilities [fresh, cryopreserved, frozen, and FT (freeze and thaw)]. The cell viabilities of fresh, cryopreserved, frozen, and FT CEs were 95.7%, 59.9%, 16.7%, and 0.0%, respectively. The four CEs had homogeneous characteristics, except for small gaps found in the FT sheet by transmission electron microscopy observation. The four CEs were applied on the full-thickness skin defect of diabetic mice (BKS.Cg-Dock 7m +/+ Leprdb/Jcl), and the wound area and neoepithelium length were evaluated on days 4, 7, and 14. As a result, FT CEs without viable cells similarly promoted epithelialization on days 4 and 7 (p<0.05) and accelerated wound closure on day 7 (p<0.01) as fresh CEs compared with the control group. In conclusion, the promoting effect of allo-CE on wound healing does not depend on cell viability. Lyophilized CEs may be a suitable wound dressing with a long storage period at room temperature., Competing Interests: I have read the journal’s policy, and the authors of this manuscript have the following competing interests: [MS and NM were financially supported by Japan Tissue Engineering Co., Ltd. (J-TEC) for their collaborating research. YS and MI were employed by J-TEC. This does not alter our adherence to PLOS ONE policies on sharing data and materials.

Corneal limbal epithelial stem cell transplantation using cultivated human corneal epithelial cell sheets has been used successfully to treat limbal stem cell deficiencies. Here we report an investigation into the quality of cultivated human corneal epithelial cell sheets using time-lapse imaging of the cell culture process every 20 minutes over 14 days to ascertain the level of cell jamming, a phenomenon in which cells become smaller, more rounded and less actively expansive. In parallel, we also assessed the expression of p63, an important corneal epithelial stem cell marker. The occurrence of cell jamming was variable and transient, but was invariably associated with a thickening and stratification of the cell sheet. p63 was present in all expanding cell sheets in the first 9 days of culture, but it's presence did not always correlate with stratification of the cell sheet. Nor did p63 expression necessarily persist in stratified cell sheets. An assessment of cell jamming, therefore, can shed significant light on the quality and regenerative potential of cultivated human corneal epithelial cell sheets.

Inherited skin disorders have been reported recently to have sporadic normal-looking areas, where a portion of the keratinocytes have recovered from causative gene mutations (revertant mosaicism). We observed a case of recessive dystrophic epidermolysis bullosa treated with cultured epidermal autografts (CEAs), whose CEA-grafted site remained epithelized for 16 years. We proved that the CEA product and the grafted area included cells with revertant mosaicism. Based on these findings, we conducted an investigator-initiated clinical trial of CEAs from clinically revertant skin for recessive dystrophic epidermolysis bullosa. The donor sites were analyzed by genetic analysis, immunofluorescence, electron microscopy, and quantification of the reverted mRNA with deep sequencing. The primary endpoint was the ulcer epithelization rate per patient at 4 weeks after the last CEA application. Three patients with recessive dystrophic epidermolysis bullosa with 8 ulcers were enrolled, and the epithelization rate for each patient at the primary endpoint was 87.7%, 100%, and 57.0%, respectively. The clinical effects were found to persist for at least 76 weeks after CEA transplantation. One of the three patients had apparent revertant mosaicism in the donor skin and in the post-transplanted area. CEAs from clinically normal skin are a potentially well-tolerated treatment for recessive dystrophic epidermolysis bullosa., (Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.)

DNA methylation is considered the primary epigenetic mechanism underlying the development of malignant melanoma. Since DNA methylation can be influenced by environmental factors, it is preferable to compare cancer and normal cells from the same patient. In order to compare the methylation status in melanoma tissues and melanocytes from the same individuals, we employed a novel epidermal sheet cultivation technique to isolate normal melanocytes from unaffected sites of melanoma patients. We also analyzed primary and metastatic melanoma samples, three commercially available melanocytes, and four melanoma cell lines. Cluster analysis of DNA methylation data classified freshly isolated melanomas and melanocytes into the same group, whereas the four melanoma cell lines were clustered together in a distant clade. Moreover, our analysis discovered methylation at several novel loci ( KRTCAP3, AGAP2, ZNF490 ), in addition to those identified in previous studies ( COL1A2, GPX3 ); however, the latter two were not observed in fresh melanoma samples. Subsequent studies revealed that NPM2 was hypermethylated and downregulated in melanomas, which was consistent with previous reports. In many normal melanocytes, NPM2 showed distinct immunohistochemical staining, while its expression was lost in malignant melanoma cells. In particular, intraepithelial lesions of malignant melanoma, an important challenge in clinical practice, could be distinguished from benign nevi. The present findings indicate the importance of using fresh melanoma samples, not melanoma cell lines and melanocytes in epigenetic studies. In addition, NPM2 immunoreactivity could be used to differentiate melanomas from normal melanocytes or benign disease.

Introduction: As the take rate of cultured epidermal autografts in burn wound treatment is variable, widely expanded meshed auto skin grafts are often used in combination with cultured epidermal autograft to increase the take rate and achieve definitive wound coverage. However, a long time (3-4 weeks) required to prepare a cultured epidermis sheet is a disadvantage. Allogeneic cultured epidermis can be prepared in advance and cryopreserved to be used in combination with auto meshed skin grafts for treating third-degree burns. Nevertheless, the human cultured epidermis (hCE) has not been proved to accelerate wound healing after meshed skin grafting. Here, we investigated the effect of hCE on wound healing in a rat model of meshed skin grafting., Materials and Methods: Human cultured epidermis was prepared from human neonatal foreskin and assessed by the release of growth factors into the culture medium using enzyme-linked immunosorbent assay. Skin wounds were inflicted on male F344 rats and treated by the application of widely meshed (6:1 ratio) autogenous skin grafts with or without hCE (n = 8 rats per group). Wound area, neoepithelium length, granulation tissue formation, and neovascularization were evaluated on day 7 postgrafting., Results: Human cultured epidermis secreted IL-1α, Basic fibroblast growth factor, platelet-derived growth factor-AA, TGF-α, TGF-β1, and vascular endothelial growth factor in vitro. In rats, hCE accelerated wound closure (P = 0.003), neoepithelium growth (P = 0.019), and granulation tissue formation (P = 0.043), and increased the number of capillaries (P = 0.0003) and gross neovascularization area (P = 0.008) compared with the control group., Conclusions: The application of hCE with meshed grafts promoted wound closure, possibly via secretion of growth factors critical for cell proliferation and migration, suggesting that hCE can enhance the healing effect of widely expanded skin autografts.

We previously reported that human nevus tissue was inactivated after high hydrostatic pressure (HHP) higher than 200 MPa and that human cultured epidermis (hCE) engrafted on the pressurized nevus at 200 MPa but not at 1000 MPa. In this study, we explore the changes to the epidermal basement membrane in detail and elucidate the cause of the difference in hCE engraftment. Nevus specimens of 8 mm in diameter were divided into five groups (control and 100, 200, 500, and 1000 MPa). Immediately after HHP, immunohistochemical staining was performed to detect the presence of laminin-332 and type VII collagen, and the specimens were observed by transmission electron microscopy (TEM). hCE was placed on the pressurized nevus specimens in the 200, 500, and 1000 MPa groups and implanted into the subcutis of nude mice; the specimens were harvested at 14 days after implantation. Then, human keratinocytes were seeded on the pressurized nevus and the attachment was evaluated. The immunohistochemical staining results revealed that the control and 100 MPa, 200 MPa, and 500 MPa groups were positive for type VII collagen and laminin-332 immediately after HHP. TEM showed that, in all of the groups, the lamina densa existed; however, anchoring fibrils were not clearly observed in the 500 or 1000 MPa groups. Although the hCE took in the 200 and 500 MPa groups, keratinocyte attachment was only confirmed in the 200 MPa group. This result indicates that HHP at 200 MPa is preferable for inactivating nevus tissue to allow its reuse for skin reconstruction in the clinical setting., Competing Interests: The authors declare that they have no competing interests in association with the present study.

Giant congenital melanocytic nevi are intractable lesions associated with a risk of melanoma. High hydrostatic pressure (HHP) technology is a safe physical method for producing decellularized tissues without chemicals. We have reported that HHP can inactivate cells present in various tissues without damaging the native extracellular matrix (ECM). The objectives of this study were to inactivate human nevus tissue using HHP and to explore the possibility of reconstructing skin using inactivated nevus in combination with cultured epidermis (CE). Human nevus specimens 8 mm in diameter were pressurized by HHP at 100, 200, 500, and 1000 MPa for 10 min. The viability of specimens just after HHP, outgrowth of cells, and viability after cultivation were evaluated to confirm the inactivation by HHP. Histological evaluation using hematoxylin-eosin staining and immunohistochemical staining for type IV collagen was performed to detect damage to the ECM of the nevus. The pressurized nevus was implanted into the subcutis of nude mice for 6 months to evaluate the retention of human cells. Then, human CE was applied on the pressurized nevus and implanted into the subcutis of nude mice. The viability of pressurized nevus was not detected just after HHP and after cultivation, and outgrowth of fibroblasts was not observed in the 200, 500, and 1000 MPa groups. Human cells were not observed after 6 months of implantation in these groups. No apparent damage to the ECM was detected in all groups; however, CE took on nevus in the 200 and 500 MPa groups, but not in the 1000 MPa group. These results indicate that human nevus tissue was inactivated by HHP at more than 200 MPa; however, HHP at 1000 MPa might cause damage that prevents the take of CE. In conclusion, all cells in nevus specimens were inactivated after HHP at more than 200 MPa and this inactivated nevus could be used as autologous dermis for covering full-thickness skin defects after nevus removal. HHP between 200 and 500 MPa will be optimal to reconstruct skin in combination with cultured epidermal autograft without damage to the ECM.

We have reported that high-hydrostatic-pressure (HHP) technology is safe and useful for producing various kinds of decellularized tissue. However, the preparation of decellularized or inactivated skin using HHP has not been reported. The objective of this study was thus to prepare inactivated skin from human skin using HHP, and to explore the appropriate conditions of pressurization to inactivate skin that can be used for skin reconstruction. Human skin samples of 8 mm in diameter were packed in bags filled with normal saline solution (NSS) or distilled water (DW), and then pressurized at 0, 100, 150, 200 and 1000 MPa for 10 minutes. The viability of skin after HHP was evaluated using WST-8 assay. Outgrowth cells from pressurized skin and the viability of pressurized skin after cultivation for 14 days were also evaluated. The pressurized skin was subjected to histological evaluation using hematoxylin and eosin staining, scanning electron microscopy (SEM), immunohistochemical staining of type IV collagen for the basement membrane of epidermis and capillaries, and immunohistochemical staining of von Willebrand factor (vWF) for capillaries. Then, human cultured epidermis (CE) was applied on the pressurized skin and implanted into the subcutis of nude mice; specimens were subsequently obtained 14 days after implantation. Skin samples pressurized at more than 200 MPa were inactivated in both NSS and DW. The basement membrane and capillaries remained intact in all groups according to histological and immunohistological evaluations, and collagen fibers showed no apparent damage by SEM. CE took on skin pressurized at 150 and 200 MPa after implantation, whereas it did not take on skin pressurized at 1000 MPa. These results indicate that human skin could be inactivated after pressurization at more than 200 MPa, but skin pressurized at 1000 MPa had some damage to the dermis that prevented the taking of CE. Therefore, pressurization at 200 MPa is optimal for preparing inactivated skin that can be used for skin reconstruction.

A reconstructed human epidermis, an in vitro model of a cultured epithelial autograft, was used to examine the formation of a stratum corneum induced by exposure to air. A prolonged wet condition and excess application of petrolatum on the dressing reduced efficient production of the stratum corneum., (Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Unlabelled: 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.

An electrogastrogram (EGG) is considered to be an index to the autonomic nervous system of the digestive organs. In the present study, we attempted to clarify whether or not an EGG can be used to evaluate the influence of illumination, and what kinds of effect taste stimuli and illumination have on the autonomic nervous system. In this study, we used the ratio of the normal wave component of the EGG (EGG-NR: 2-4.5 cpm power/1-10 cpm power) and the amplitude of a normal wave (EGG-NI: integrated EGG of 2-4.5 cpm). Thirteen healthy males participated in 16 experimental conditions (4 lighting conditionsx4 taste stimuli). The four lighting conditions were set by combinations of illuminance levels of 200 and 1500 lx and color temperatures of 3000 and 7500 K. The four taste stimuli were sweet (glucose), salty (salt), sour (acetic acid), and bitter (quinine). The changes in EGG-NR and EGG-NI were compared for different taste conditions. The results showed that EGG-NI was not significantly affected by the different taste conditions. However, the main effect of taste on EGG-NR was significant: sweet and salty tastes were significantly higher than the bitter taste. EGG-NR and EGG-NI in different lighting conditions were also compared. The main effect of different color temperatures was also significant, but the illuminance level did not affect EGG-NR. EGG-NR increased significantly at the lower color temperature. On the other hand, EGG-NI significantly increased at the lower illuminance. These results suggest that parasympathetic nervous activity has a predominant effect on gastric activity in different lighting environments. Therefore, EGG measurements may be useful indicators for illumination environment studies.

The serial subculturing of human keratinocyte cells under the anoxic and normoxic conditions was examined. The cumulative number of population doublings in the subcultures under the former condition increased 2.1-fold while maintaining an appreciable growth rate of cells, as compared with that under the latter condition. Moreover, the migration ability, which was estimated by the rotation rate of paired cells, was maintained accompanied by fully developed filopodia of F-actin filaments under the anoxic condition, despite of the poor development of stress fibers at the center of the cellular body. The cells passaged under the anoxic condition possessed the sufficient clonogenic potential to form epithelial sheets, supporting the view that the long-term subculture of keratinocytes under the anoxic condition can be applied for cell expansion in the practical production of epithelial sheets.

Cultured epidermal autografting has been employed in a variety of clinical treatments including vitiligo management. In this study, we successfully treated 2 patients with vitiligo using a short-pulsed CO2 laser and by grafting the autologous cultured epidermis. Small pieces of uninvolved skin (2 x 1 cm) were taken for cultivation from a pudendal or axillary area and were expanded into 2 pieces of epidermal sheets 100 cm. Before grafting, the lesions were abraded superficially using a short-pulsed CO2 laser with a computerized pattern generator. After successful grafting, repigmentation was visible within 1 to 2 months. One year after grafting, the skin color was almost the same as that of the surrounding normal skin. Thus, the combination of short-pulsed CO2 laser resurfacing and cultured epidermal grafting is a powerful option for treating an asymmetric and wide vitiliginous lesion.

Histamine H2 receptor antagonism by T-593 was investigated in Hepa cells expressing canine histamine H2 receptors. T-593 inhibited generation of cAMP in Hepa cells stimulated by 10(-5) mol/l histamine with an IC50 value of 2.3 x 10(-6) mol/l, (S)-(-)-T-593, one of the enantiomers comprising racemic T-593, inhibited cAMP generation with an IC50 value of 6.1 x 10(-7) mol/l. On the other hand, the other enantiomer (R)-(+)-T-593 exhibited only a negligible effect. Incubation of the cell with (S)-(-)-T-593 for 60 min depressed the maximal response of the concentration-response curve of histamine with a nonparallel rightward shift. The slope of a Schild plot was 1.27. In contrast, (S)-(-)-T-593 caused a parallel rightward shift of the curve, with a Schild plot slope that did not significantly differ from unity, by treating the cells for 15 min. The H2 receptor-blocking action of (S)-(-)-T-593 remained almost unaffected after washing out the drug, whereas the effect of ranitidine was reversible after washing. These results suggest that T-593 possesses a time-dependent insurmountable antagonistic action against histamine H2 receptor. T-593 may interact with the histamine H2 receptor molecule in a slowly associable and dissociable manner.

Histamine H2-receptor antagonistic properties of the anti-ulcer agent T-593, (+/-)-(E)-1-[2-hydroxy-2-(4-hydroxyphenyl)ethyl] -3-[2[[[5-(methylamino)methyl-2-furyl]methyl]thio] ethyl] -2-(methylsulfonyl)guanidine, were investigated on [14C]aminopyrine accumulation in isolated canine gastric mucosal cells and compared with those of ranitidine and famotidine. The potency of T-593-inhibition of [14C]aminopyrine accumulation stimulated by 10(-4) M histamine, with an IC50 value of 1.85 x 10(-6) M, was approximately 5 times greater than that of ranitidine, but half that of famotidine. T-593 did not affect [14C]aminopyrine accumulation stimulated by carbachol or dibutyryl-cAMP. T-593 depressed the maximal response of the histamine concentration-response curve with a dose-related displacement to the right, indicating that the nature of the H2-receptor antagonism of T-593 was insurmountable and included non-competitive inhibition. The inhibitory efficacy of T-593 was time-dependent and was retained after the cells were washed. The inhibitory potency of (-)-S-T-593, one of the enantiomers, on the [14C]aminopyrine accumulation stimulated by histamine was approximately twice that of racemic T-593 and it also behaved as an insurmountable H2-receptor antagonist. However, the potency of (+)-R-T-593 was markedly weak. These results suggest that T-593 has H2-receptor antagonism that is insurmountable and this agent slowly associates and dissociates with the receptor in isolated canine gastric mucosal cells and that the specific substance causing H2-receptor antagonism is (-)-S-T-593.