Effect of Chicken Age on Proliferation and Differentiation Abilities of Muscle Stem Cells and Nutritional Characteristics of Cultured Meat Tissue.

This study aimed to investigate effects of chicken age on proliferation and differentiation capacity of muscle satellite cells (MSCs) and to determine total amino acid contents of cultured meat (CM) produced. Chicken MSCs (cMSCs) were isolated from hindlimb muscles of broiler chickens at 5-week-old (5W) and 19-embryonic-day (19ED), respectively. Proliferation abilities (population doubling time and cell counting kit 8) of cMSCs from 19ED were significantly higher than those from 5W (p<0.05). Likewise, both myotube formation area and expression of myosin heavy chain heavy of cMSCs from 19ED were significantly higher than those from 5W (p<0.05). After cMSCs were serially subcultured for long-term cultivation in 2D flasks to produce cultured meat tissue (CMT), total amino acid contents of CMT showed no significant difference between 5W and 19ED chickens (p>0.05). This finding suggests that cMSCs from chicken embryos are more suitable for improving the production efficiency of CM than those derived from young chickens.

Comparison of Soy and Pea Protein for Cultured Meat Scaffolds: Evaluating Gelation, Physical Properties, and Cell Adhesion.

Cultured meat is under investigation as an environmentally sustainable substitute for conventional animal-derived meat. Employing a scaffolding technique is one approach to developing cultured meat products. The objective of this research was to compare soy and pea protein in the production of hydrogel scaffolds intended for cultured meat. We examined the gelation process, physical characteristics, and the ability of scaffolds to facilitate cell adhesion using mesenchymal stem cells derived from porcine adipose tissue (ADSCs). The combination of soy and pea proteins with agarose and agar powders was found to generate solid hydrogels with a porous structure. Soy protein-based scaffolds exhibited a higher water absorption rate, whereas scaffolds containing agarose had a higher compressive strength. Based on Fourier transform infrared spectroscopy analysis, the number of hydrophobic interactions increased between proteins and polysaccharides in the scaffolds containing pea proteins. All scaffolds were nontoxic toward ADSCs, and soy protein-based scaffolds displayed higher cell adhesion and proliferation properties. Overall, the soy protein-agarose scaffold was found to be optimal for cultured meat production.

Additional treatments after curettage of congenital melanocytic nevi in the craniofacial region: A report from a single center in Japan.

BACKGROUND: Congenital melanocytic nevus (CMN) is a benign skin lesion present from birth, which may present with a risk of malignant transformation if extensive. Curettage, a treatment method involving the removal of the superficial layer of the nevus, is often used in the early stages of life. However, recurrence of the nevus and postoperative scarring may present as problems. Additional treatments, such as resection and/or laser treatment, are regularly required after curettage, particularly in the craniofacial region. However, no systematic treatment strategy has been reported. This study investigated additional treatments used after curettage to treat CMN in the craniofacial region and compared the frequency of treatments with respect to specific sites. METHODS: CMN cases involving curettage as an initial treatment were retrospectively reviewed at Kyoto University Hospital between May 2019 and April 2022. RESULTS: This study comprised 23 cases. Curettage was performed at a mean of 3.8 (1-10) months of age. No additional treatments were provided for 80% of head CMN. Additional treatments were performed in all cases, including the forehead and cheek. Laser treatment was performed in 86% of eyelid CMN and 75% of nasal CMN. Tissue expansion and flap closure were used in 33% of forehead CMN and 33% of cheek CMN. CONCLUSIONS: Additional treatments used for CMN in the craniofacial region varied in accordance with the lesion site.

Occurrence and risk assessment of quinolones and sulfonamides in freshwater aquaculture ponds in Northeast Zhejiang, China.

Antibiotics play an essential role in the aquaculture industry, but their overuse and weak degradability inevitably lead to light to severe residues in natural and aquaculture environments. Most studies were interested in the occurrence, distribution, and ecological risks of a limited number of antibiotics in natural environments (rivers, lakes, and coastal regions) with a minor focus on antibiotic presence in either water, sediments, or organisms in aquaculture environments located in specific regions. In this study, we conducted a comprehensive investigation into the occurrence and distribution of up to 32 antibiotics [including 15 quinolones (QNs) and 17 sulfonamides (SAs)] in organisms and their corresponding environmental matrices from 26 freshwater aquaculture ponds in Northeast Zhejiang, China. A total of 13, 9, 7, and 7 antibiotics were detected in pond water, sediments, feeds, and aquaculture organisms, respectively, with concentration ranges of 0.6-92.2 ng/L, 0.4-1169.3 ng/g dw,

Comprehensive scRNA-seq analysis to identify new markers of M2 macrophages for predicting the prognosis of prostate cancer.

BACKGROUND: Prostate cancer (PCa) has become the highest incidence of malignant tumor among men in the world. Tumor microenvironment (TME) is necessary for tumor growth. M2 macrophages play an important role in many solid tumors. This research aimed at the role of M2 macrophages' prognosis value in PCa. METHODS: Single-cell RNA-seq (scRNA-seq) data and mRNA expression data were obtained from the Gene Expression Omnibus database (GEO) and The Cancer Genome Atlas (TCGA). Quality control, normalization, reduction, clustering, and cell annotation of scRNA-seq data were preformed using the Seruat package. The sub-populations of the tumor-associated macrophages (TAMs) were analysis and the marker genes of M2 macrophage were selected. Differentially expressed genes (DEGs) in PCa were identified using limma and the immune infiltration was detected using CIBERSORTx. Then, a weighted correlation network analysis (WGCNA) was constructed to identify the M2 macrophage-related modules and genes. Integration of the marker genes of M2 macrophage from scRNA-seq data analysis and hub genes from WGCNA to select the prognostic gene signature based on Univariate and LASSO regression analysis. The risk score was calculated, and the DEGs, biological function, immune characteristics related to risk score were explored. And a predictive nomogram was constructed. CCK8, Transwell, and wound healing were used to verify cell phenotype changes after co-cultured. RESULTS: A total of 2431 marker genes of M2 macrophage and 650 hub M2 macrophage-related genes were selected based on scRNA-seq data and WGCNA. Then, 113 M2 macrophage-related genes were obtained by overlapping the scRNA-seq data and WGCNA results. Nine M2 macrophage-related genes (SMOC2, PLPP1, HES1, STMN1, GPR160, ABCG1, MAZ, MYC, and EPCAM) were screened as prognostic gene signatures. M2 risk score was calculated, the DEGs, Immune score, stromal score, ESTIMATE score, tumor purity, and immune cell infiltration, immune checkpoint expression, and responses of immunotherapy and chemotherapy were identified. And a predictive nomogram was constructed. CCK8, Transwell invasion, and wound healing further verified that M2 macrophages promoted the proliferation, invasion, and migration of PCa (p < 0.05). CONCLUSIONS: We uncovered that M2 macrophages and relevant genes played key roles in promoting the occurrence, development, and metastases of PCa and played as convincing predictors in PCa.

Optimization of differentiation conditions for porcine adipose-derived mesenchymal stem cells and analysis of fatty acids in cultured fat.

Cultured fat is an important part of cultured meat, and the ability of adipose-derived mesenchymal stem cells (ADSCs) to differentiate into mature adipose tissue affects the quality of cultured fat. Thus, the primary aim of this study was to screen for combinations of differentiation-inducing factors (DIF) using single-factor experiment and orthogonal experimental design under two-dimensional culture conditions for ADSCs. The results showed that a combination of DIF consisting of 1 µmol/L dexamethasone, 0.1 mmol/L 3-isobutyl-1-methylxanthine, 10 µg/mL insulin, 0.1 mmol/L indomethacin, and 2 µmol/L rosiglitazone was a good choice for the differentiation of ADSCs. An combination of DIF was applied to the preparation of cultured fat with collagen as scaffolds. Forty-eight fatty acids were detected in cultured fat by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). Among them, the content of twenty-one fatty acids in cultured fat was significantly higher than that of conventional porcine subcutaneous adipose tissue (P < 0.05), and the content of 14 fatty acids was not significantly different (P > 0.05). The ratio of ω-6 polyunsaturated fatty acids content to ω-3 polyunsaturated fatty acids content was 1.23:1, which meant cultured fat was beneficial for human health. This study provides a method to improve the differentiation ability of ADSCs while also providing a reference for indicating the nutritional value of cultured fat.

A new diphenyl ether from the cultured lichen mycobiont of Graphis cf. handelii.

Lichen is well-known for its various purposes. However, understanding the chemical composition and antimicrobial characteristics of Graphis cf. handelii remains insufficient. In this study, a new compound, graphinone A (1), together with three known compounds, handelone (2), 4-O-methylhiascic acid (3), and ethyl orsellinate (4) were isolated and structurally elucidated. Their chemical structures were established using comprehensive spectroscopic data (1D- and 2D-NMR and HRESIMS). Compounds 1-4 were tested for antimicrobial activity against methicillin-resistant Staphylococcus aureus (MRSA) and evaluated for the alpha-glucosidase inhibition.

Simultaneous determination of canonical purine metabolism using a newly developed HILIC-MS/MS in cultured cells.

Purine metabolism acts as the core role in human metabolic network. It offers purine metabolites as raw material for building blocks in cell survival and proliferation. Purine metabolites are the most abundant metabolic substrates in organisms. There are few reports to simultaneously quantify canonical purine metabolism in cells. A novel hydrophilic interaction liquid chromatography coupled with mass spectrometry (HILIC-MS/MS) method was developed to simultaneously determine purines profile in biological samples. Chromatographic separation was achieved using a HILIC (Waters Xbridge™ Amide) column. Different optimizing chromatographic conditions and mass spectrometric parameters were tested in order to provide the best separation and the lowest limit of quantification (LLOQ) values for targeted metabolites. The validation was evaluated according to the Food and Drug Administration guidelines. The limit of determination (LOD) and the LOQ values were in the range of 0.02-8.33 ng mL-1 and 0.1-24.5 ng mL-1, respectively. All calibration curves displayed good linear relationship of with excellent correlation coefficient (r) ranging from 0.9943 to 0.9999. Both intra-day and inter-day variability were below 15 %, respectively. Trueness, expressed as relative error, was always within ±15 %. In addition, no derivatization procedure and ion-pair reagents are in need. The innovated approach demonstrates high sensitivity, strong specificity, and good repeatability, making it suitable for absolute quantitative studies of canonical purine metabolism in cultured cells.

Establishment, characterization, and sensory characteristics (taste and flavor) of an immortalized muscle cell line from the seven-band grouper Epinephelus septemfasciatus: implications for cultured seafood applications.

Grouper muscle satellite cells (GMSCs) from the seven-band grouper (Epinephelus septemfasciatus) were isolated, and their growth conditions were optimized (10% fetal bovine serum, 24°C, 10 ng/mL bFGF). The cells were immortalized at passage 14 and designated as grouper immortalized muscle satellite cells (GIMSCs). DNA barcoding confirmed the grouper origin of both GMSC and GIMSC lines. GIMSCs exhibited enhanced proliferation, accelerated differentiation, and robust myotube formation compared to pre-crisis GMSCs. Western blot analysis showed upregulation of key myogenic factors (Pax7, MyoD, MyoG) and structural proteins (Desmin) in GIMSC, indicating the differentiation potential. The immortalized GIMSC line maintained consistent morphology, growth rates, and viability across multiple passages. Biocompatibility studies showed GIMSCs were compatible with bio-inks (sodium alginate, gelatin, κ-carrageenan) at 250 to 10,000 µg/mL, retaining ~ 80% viability at the highest concentration. Taste sensory analysis revealed GMSCs had the highest umami and lowest saltiness and sourness, contrasting with the muscle of the seven-band grouper, which had higher saltiness and sourness. Flavor analysis identified pronounced fishy, hot fat, and ethereal flavors in the cells at higher level than in the muscle. These findings suggest GMSCs and GIMSCs are promising for producing cultured meat with enhanced umami taste and flavors, advancing cellular agriculture and sustainable food production.

PROTAC-mediated vimentin degradation promotes terminal erythroid differentiation of pluripotent stem cells.

BACKGROUND: Human pluripotent stem cells (hPSCs), including human embryonic stem cells (hESCs) and induced pluripotent stem cells (hiPSCs), can undergo erythroid differentiation, offering a potentially invaluable resource for generating large quantities of erythroid cells. However, the majority of erythrocytes derived from hPSCs fail to enucleate compared with those derived from cord blood progenitors, with an unknown molecular basis for this difference. The expression of vimentin (VIM) is retained in erythroid cells differentiated from hPSCs but is absent in mature erythrocytes. Further exploration is required to ascertain whether VIM plays a critical role in enucleation and to elucidate the underlying mechanisms. METHODS: In this study, we established a hESC line with reversible vimentin degradation (dTAG-VIM-H9) using the proteolysis-targeting chimera (PROTAC) platform. Various time-course studies, including erythropoiesis from CD34+ human umbilical cord blood and three-dimensional (3D) organoid culture from hESCs, morphological analysis, quantitative real-time PCR (qRT-PCR), western blotting, flow cytometry, karyotyping, cytospin, Benzidine-Giemsa staining, immunofluorescence assay, and high-speed cell imaging analysis, were conducted to examine and compare the characteristics of hESCs and those with vimentin degradation, as well as their differentiated erythroid cells. RESULTS: Vimentin expression diminished during normal erythropoiesis in CD34+ cord blood cells, whereas it persisted in erythroid cells differentiated from hESC. Depletion of vimentin using the degradation tag (dTAG) system promotes erythroid enucleation in dTAG-VIM-H9 cells. Nuclear polarization of erythroblasts is elevated by elimination of vimentin. CONCLUSIONS: VIM disappear during the normal maturation of erythroid cells, whereas they are retained in erythroid cells differentiated from hPSCs. We found that retention of vimentin during erythropoiesis impairs erythroid enucleation from hPSCs. Using the PROTAC platform, we validated that vimentin degradation by dTAG accelerates the enucleation rate in dTAG-VIM-H9 cells by enhancing nuclear polarization.

Cultured fecal microbial community and its impact as fecal microbiota transplantation treatment in mice gut inflammation.

The fecal microbiome is identical to the gut microbial communities and provides an easy access to the gut microbiome. Therefore, fecal microbial transplantation (FMT) strategies have been used to alter dysbiotic gut microbiomes with healthy fecal microbiota, successfully alleviating various metabolic disorders, such as obesity, type 2 diabetes, and inflammatory bowel disease (IBD). However, the success of FMT treatment is donor-dependent and variations in gut microbes cannot be avoided. This problem may be overcome by using a cultured fecal microbiome. In this study, a human fecal microbiome was cultured using five different media; growth in brain heart infusion (BHI) media resulted in the highest microbial community cell count. The microbiome (16S rRNA) data demonstrated that the cultured microbial communities were similar to that of the original fecal sample. Therefore, the BHI-cultured fecal microbiome was selected for cultured FMT (cFMT). Furthermore, a dextran sodium sulfate (DSS)-induced mice-IBD model was used to confirm the impact of cFMT. Results showed that cFMT effectively alleviated IBD-associated symptoms, including improved gut permeability, restoration of the inflamed gut epithelium, decreased expression of pro-inflammatory cytokines (IFN-γ, TNF-α, IL-1, IL-6, IL-12, and IL-17), and increased expression of anti-inflammatory cytokines (IL-4 and IL-10). Thus, study's findings suggest that cFMT can be a potential alternative to nFMT. KEY POINTS: • In vitro fecal microbial communities were grown in a batch culture using five different media. • Fecal microbial transplantation was performed on DSS-treated mice using cultured and normal fecal microbes. • Cultured fecal microbes effectively alleviated IBD-associated symptoms.

Botanical-induced toxicity: liver injury and botanical-drug interactions A report on a Society of Toxicology Annual Meeting symposium.

Botanical supplements and herbal products are widely used by consumers for various purported health benefits, and their popularity is increasing. Some of these natural products can have adverse effects on liver function and/or interact with prescription and over-the-counter (OTC) medications. Ensuring the safety of these readily available products is a crucial public health concern; however, not all regulatory authorities require premarket safety review and/or testing. To address and discuss these and other emerging needs related to botanical safety, a symposium was held at the Society of Toxicology Annual Meeting in Salt Lake City (UT) on March 11, 2024. The symposium addressed the latest research on botanical-induced liver toxicity and botanical-drug interactions, including new approach methods to screen for toxicity, challenges in assessing the safety of botanicals, and relating human adverse events to specific products. The presentations and robust panel discussion between the speakers and audience highlighted the need for further research and collaboration to improve the safety of botanical supplements and herbal products, with the ultimate goal of protecting consumer health. Although utility of many of the modern tools presented in the symposium requires further study, the synergistic efforts of diverse experts hold promise for effective prediction and evaluation of botanical-induced hepatotoxicity and botanical-drug interaction potential.

A narrative review: 3D bioprinting of cultured muscle meat and seafood products and its potential for the food industry.

The demand for meat and seafood products has been globally increasing for decades. To address the environmental, social, and economic impacts of this trend, there has been a surge in the development of three-dimensional (3D) food bioprinting technologies for lab-grown muscle food products and their analogues. This innovative approach is a sustainable solution to mitigate the environmental risks associated with climate change caused by the negative impacts of indiscriminative livestock production and industrial aquaculture. This review article explores the adoption of 3D bioprinting modalities to manufacture lab-grown muscle food products and their associated technologies, cells, and bioink formulations. Additionally, various processing techniques, governing the characteristics of bioprinted food products, nutritional compositions, and safety aspects as well as its relevant ethical and social considerations, were discussed. Although promising, further research and development is needed to meet standards and translate into several industrial areas, such as the food and renewable energy industries. In specific, optimization of animal cell culture conditions, development of serum-free media, and bioreactor design are essential to eliminate the risk factors but achieve the unique nutritional requirements and consumer acceptance. In short, the advancement of 3D bioprinting technologies holds great potential for transforming the food industry, but achieving widespread adoption will require continued innovation, rigorous research, and adherence to ethical standards to ensure safety, nutritional quality, and consumer acceptance.

A serum-free culture medium production system by co-culture combining growth factor-secreting cells and L-lactate-assimilating cyanobacteria for sustainable cultured meat production.

Large-scale production of cultured meat requires bulk culture medium containing growth-promoting proteins from animal serum. However, animal serum for mammalian cell culture is associated with high costs, ethical concerns, and contamination risks. Owing to its growth factor content, conditioned medium from rat liver epithelial RL34 cells can replace animal serum for myoblast proliferation. More seeded cells and longer culture periods are thought to yield higher growth factor levels, resulting in more effective muscle cell proliferation. However, RL34 cells can deplete nutrients and release harmful metabolites into the culture medium over time, potentially causing growth inhibition and apoptosis. This issue highlights the need for waste clearance during condition medium production. To address this issue, we introduced a lactate permease gene (lldP) and an L-lactate-to-pyruvate conversion enzyme gene (lldD) to generate a recombinant L-lactate-assimilating cyanobacterium Synechococcus sp. KC0110 strain. Transwell co-culture of this strain with RL34 cells exhibited a marked reduction in the levels of harmful metabolites, lactate and ammonium, while maintaining higher concentrations of glucose, pyruvate, and pyruvate-derived amino acids than those seen with RL34 cell monocultures. The co-culture medium supported myoblast proliferation without medium dilution or additional nutrients, which was attributed to the waste clearance and nutrient replenishment effects of the KC0110 strain. This culture system holds potential for the production of low-cost, and animal-free cultured meat.

A rich-nutritious cultured meat via bovine myocytes and adipocytes co-culture: Novel Prospect for cultured meat production techniques.

Cultured meat, an emerging meat production technology, has reduced environmental burden as well as provide healthier and more sustainable method of meat culture. Fat in cultured meat is essential for enhancing texture, taste, and tenderness. However, current cultured meat production method is limited to single-cell type. To meet the consumer demands for cultured meat products, it is crucial to develop new methods for producing cultured meat products that contain both muscle and fat. In this study, cell viability and differentiation were promoted by controlling the ratio and cultivation conditions of myocytes and adipocytes. The total digestibility of cultured meat exceeded 37%, higher than that of beef (34.7%). Additionally, the texture, appearance, and taste of the co-cultured meat were improved. Collectively, this research has great promise for preparing rich-nutritious and digestion cultured meat.

Graft take outcomes of burn patients transplanted with CEA derived from a modified composite culture technique: A case series.

Low-cost and efficient culture environments comparable to standard techniques would undoubtedly improve burn outcomes in under-resourced settings. The aim of this case series was to report on the CEA graft-take using a modified composite culture technique. CEA transplants, following emergency ethical approval, occurred for burn patients (n=25) with low survival prognosis and/or exhausted donor sites. Keratinocytes were retrieved from skin biopsies, seeded centrally on routinely-used dressing gauze and incubated at 37 °C in pediatric incubators. Fresh autogenous plasma was applied daily and hydrogel every third or fourth day. After confluence, the CEA was transplanted onto debrided wound beds. Xenografts were used for temporary cover during the culture period. Final graft take assessment (21 days) was assessed and calculated as a graft take percentage for total CEA area transplanted. Central indices were described as mean (95% CI) and frequency (%) for age, total body surface area, abbreviated burn severity index scores, survival prognosis and graft take. Eleven patients survived with a mean age of 36.1 years (95% CI 25.8-46.4), 45.0 %TBSA burns (95% CI 35.1-54.9), 9.7 ABSI scores (95% CI 8.6-10.8) and 79.5% graft take (95% CI 62.9-96.0). Reduced graft take (61.2%) was observed in patients with perineum burns and increased graft take (97%) in uncomplicated burns. The average CEA graft take was 79.5% using a low-cost culture technique and comparable to the largest case series in literature. The survival of the major burn cases was highly favourable considering injury severity, expected outcomes without CEA and the observed challenges.

Innovative Food Safety Approaches and Nutraceuticals to Promote Children's Health on Future Outbreaks with the Reflection of COVID-19.

After the COVID-19 pandemic, innovative methods have emerged for the management of food safety, child nutrition has become more important than ever, and increasing attention has been paid to the consequences of COVID-19. For instance, since SARS-CoV-2 is an animal-based zoonotic virus, there is a changing trend in consumer preferences from conventional meat products to cultured meat and vegan supplementation. Due to the effects mentioned, this chapter provides strategic guidance on novel foods, food safety innovations, and novel health and safety procedures in public places such as restaurants or bars. There are also long-term health impacts on children in the aftermath of COVID-19. Since the risk of myopia is one of the important long-term effects to be considered, trending nutritional immunology approaches are presented to reduce emerging problems in child eye health. The enhancement of immune system remains problematic for many children considering that they cannot use the COVID-19 vaccine. Therefore, this chapter also emphasizes the importance of breastfeeding on the side effects of viral infections and new supplements, such as probiotic drops, to improve children's and babies' immune health. Additionally, efforts should be undertaken to improve nanoencapsulation techniques to prepare for future epidemics and pandemics. Nanomaterial-supported nutraceuticals, nanoencapsulation of functional ingredients or their nanoparticles, and nano-combination of phytochemicals, fatty acids, or probiotics should be investigated to improve the immunity of children. In this sense, detailed further research in this area needs to be adapted to innovative technologies for the treatment of infants and children against future zoonotic viruses.

Plant-derived leaf vein scaffolds for the sustainable production of dog cell-cultured meat.

Animal cell culture technology in the production of slaughter-free meat offers ethical advantages with regards to animal welfare, rendering it a more socially acceptable approach for dog meat production. In this study, edible plant-derived scaffold was used as a platform for cell expansion to construct cell-cultured dog meat slices. Primary dog skeletal muscle satellite cells (MSCs) and adipose stem cells (ASCs) were isolated and cultured as seed cells, and 3D spheroid culture in vitro promoted MSCs and ASCs myogenic and adipogenic differentiation, respectively. Natural leaf veins (NLV) were produced as edible mesh scaffolds to create 3D engineered dog muscle and fat tissues. After MSCs and ASCs adhered, proliferated and differentiated on the NLV scaffolds, and muscle and fat slices were produced with cultured dog muscle fibers and adipocytes, respectively. These findings demonstrate the potential of plant-derived NLV scaffolds in the production of cultured dog meat.

An Enzyme-Free Method for Isolation and Expansion of Muscle Stem Cells for Cultivated Meat Applications.

Cultivated meat, an alternative to conventional meat, holds great promise in alleviating environmental and ethical concerns. Skeletal muscle stem cell isolation is a critical phase in cultivated meat production, and efficiency is a major determinant in the final differentiated muscle cell yield. The conventional enzymatic dissociation method for cell isolation presents drawbacks, including added costs and the destruction of vital extracellular matrix components. We developed an alternative cell isolation technique, explant cell isolation, to isolate muscle stem cells from muscle tissue. The present protocol yields myogenic cell populations, mainly composed of skeletal muscle stem cells without the use of enzymes, and through a simplified process. Overall, the explant method allows for propagation of cells in their natural environment, preserving intricate cell-cell and cell-matrix interactions, resulting in both economic efficiency and consistent generation of high-quality cells.

Long-term outcomes of a cultured autologous dermo-epidermal skin substitute in children: 5 year results of a phase I clinical trial.

Limited donor sites and poor long-term outcomes with standard treatment for large skin defects remain a huge problem. An autologous, bilayered, laboratory-grown skin substitute (denovoSkin™) was developed to overcome this problem and has shown to be safe in ten pediatric patients in a phase I clinical trial after transplantation. The goal of this article is to report on 48 months long-term results. The pediatric participants of the phase I clinical trial were followed at yearly visits up to five years after transplantation. Safety parameters including occurrence of adverse events, possible deviations of vital signs and changes in concomitant therapy as well as additional parameters regarding skin stability, scar quality and tumor formation were assessed. Furthermore, scar maturation was photographically documented. From the ten patients treated with denovoSkinTM in this phase I clinical trial, seven completed the five-year follow-up period. Skin substitutes continued to be deemed safe, remained stable and practically unchanged, with no sign of fragility, and no tumor formation at clinical examination. Scar quality, captured by applying the Patient and Observer Scar Assessment Scale, was evaluated as close to normal skin. Transplantation of this laboratory-grown skin substitute in children is to date considered safe and shows encouraging functional and aesthetical long-term results close to normal skin. These results are promising and highlight the potential of a life-saving therapy for large skin defects. A multicentre, prospective, randomized phase II clinical trial to further evaluate the safety and efficacy of this novel skin substitute is currently ongoing.