BACKGROUND: Embryos are regeneration and wound healing masters. They rapidly close wounds and scarlessly remodel and regenerate injured tissue. Regeneration has been extensively studied in many animal models using new tools such as single-cell analysis. However, until now, they have been based primarily on experiments assessing from 1 day post injury. RESULTS: In this paper, we reveal that critical steps initiating regeneration occur within hours after injury. We discovered the regeneration initiating cells (RICs) using single-cell and spatial transcriptomics of the regenerating Xenopus laevis tail. RICs are formed transiently from the basal epidermal cells, and their expression signature suggests they are important for modifying the surrounding extracellular matrix thus regulating development. The absence or deregulation of RICs leads to excessive extracellular matrix deposition and defective regeneration. CONCLUSION: RICs represent a newly discovered transient cell state involved in the initiation of the regeneration process.

• Keywords
• Xenopus laevis, RICs, ROCs, Regeneration,
• MeSH
• Single-Cell Analysis MeSH
• Extracellular Matrix metabolism   MeSH
• Wound Healing MeSH
• Tail * MeSH
• Regeneration * MeSH
• Transcriptome MeSH
• Xenopus laevis * MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH

We focused on polydimethylsiloxane (PDMS) as a substrate for replication, micropatterning, and construction of biologically active surfaces. The novelty of this study is based on the combination of the argon plasma exposure of a micropatterned PDMS scaffold, where the plasma served as a strong tool for subsequent grafting of collagen coatings and their application as cell growth scaffolds, where the standard was significantly exceeded. As part of the scaffold design, templates with a patterned microstructure of different dimensions (50 × 50, 50 × 20, and 30 × 30 μm2) were created by photolithography followed by pattern replication on a PDMS polymer substrate. Subsequently, the prepared microstructured PDMS replicas were coated with a type I collagen layer. The sample preparation was followed by the characterization of material surface properties using various analytical techniques, including scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS). To evaluate the biocompatibility of the produced samples, we conducted studies on the interactions between selected polymer replicas and micro- and nanostructures and mammalian cells. Specifically, we utilized mouse myoblasts (C2C12), and our results demonstrate that we achieved excellent cell alignment in conjunction with the development of a cytocompatible surface. Consequently, the outcomes of this research contribute to an enhanced comprehension of surface properties and interactions between structured polymers and mammalian cells. The use of periodic microstructures has the potential to advance the creation of novel materials and scaffolds in tissue engineering. These materials exhibit exceptional biocompatibility and possess the capacity to promote cell adhesion and growth.

• Keywords
• PDMS, coating, collagen type I, cytocompatibility, microstructure, myoblast cell, nanostructured pattern, replication, soft lithography,
• MeSH
• Cell Adhesion MeSH
• Dimethylpolysiloxanes chemistry   MeSH
• Collagen * chemistry   MeSH
• Myoblasts MeSH
• Mice MeSH
• Surface Properties MeSH
• Mammals MeSH
• Tissue Engineering * MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Dimethylpolysiloxanes MeSH
• Collagen * MeSH

Epidermal stem cells (ESCs) are crucial for maintenance and self- renewal of skin epithelium and also for regular hair cycling. Their role in wound healing is also indispensable. ESCs reside in a defined outer root sheath portion of hair follicle-also known as the bulge region. ECS are also found between basal cells of the interfollicular epidermis or mucous membranes. The non-epithelial elements such as mesenchymal stem cell-like elements of dermis or surrounding adipose tissue can also contribute to this niche formation. Cancer stem cells (CSCs) participate in formation of common epithelial malignant diseases such as basal cell or squamous cell carcinoma. In this review article, we focus on the role of cancer microenvironment with emphasis on the effect of cancer-associated fibroblasts (CAFs). This model reflects various biological aspects of interaction between cancer cell and CAFs with multiple parallels to interaction of normal epidermal stem cells and their niche. The complexity of intercellular interactions within tumor stroma is depicted on example of malignant melanoma, where keratinocytes also contribute the microenvironmental landscape during early phase of tumor progression. Interactions seen in normal bulge region can therefore be an important source of information for proper understanding to melanoma. The therapeutic consequences of targeting of microenvironment in anticancer therapy and for improved wound healing are included to article.

• Keywords
• cancer microenvironment, cancer-associated fibroblast, niche, stem cell, wound healing,
• MeSH
• Epidermal Cells MeSH
• Epithelial Cells pathology   MeSH
• Fibroblasts pathology   MeSH
• Wound Healing physiology   MeSH
• Keratinocytes pathology   MeSH
• Humans MeSH
• Melanoma pathology   MeSH
• Mesenchymal Stem Cells pathology   MeSH
• Neoplastic Stem Cells pathology   MeSH
• Tumor Microenvironment physiology   MeSH
• Skin Neoplasms pathology   MeSH
• Stem Cell Niche physiology   MeSH
• Hair Follicle cytology   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH

BACKGROUND: Nodular melanoma is one of the most life threatening tumors with still poor therapeutic outcome. Similarly to other tumors, permissive microenvironment is essential for melanoma progression. Features of this microenvironment are arising from molecular crosstalk between the melanoma cells (MC) and the surrounding cell populations in the context of skin tissue. Here, we study the effect of melanoma cells on human primary keratinocytes (HPK). Presence of MC is as an important modulator of the tumor microenvironment and we compare it to the effect of nonmalignant lowly differentiated cells also originating from neural crest (NCSC). METHODS: Comparative morphometrical and immunohistochemical analysis of epidermis surrounding nodular melanoma (n = 100) was performed. Data were compared to results of transcriptome profiling of in vitro models, in which HPK were co-cultured with MC, normal human melanocytes, and NCSC, respectively. Differentially expressed candidate genes were verified by RT-qPCR. Biological activity of candidate proteins was assessed on cultured HPK. RESULTS: Epidermis surrounding nodular melanoma exhibits hyperplastic features in 90% of cases. This hyperplastic region exhibits aberrant suprabasal expression of keratin 14 accompanied by loss of keratin 10. We observe that MC and NCSC are able to increase expression of keratins 8, 14, 19, and vimentin in the co-cultured HPK. This in vitro finding partially correlates with pseudoepitheliomatous hyperplasia observed in melanoma biopsies. We provide evidence of FGF-2, CXCL-1, IL-8, and VEGF-A participation in the activity of melanoma cells on keratinocytes. CONCLUSION: We conclude that the MC are able to influence locally the differentiation pattern of keratinocytes in vivo as well as in vitro. This interaction further highlights the role of intercellular interactions in melanoma. The reciprocal role of activated keratinocytes on biology of melanoma cells shall be verified in the future.

• MeSH
• Cell Differentiation * genetics   MeSH
• Chemokine CXCL1 pharmacology   MeSH
• Adult MeSH
• Epidermal Cells * MeSH
• Epidermis pathology   MeSH
• Fibroblast Growth Factor 2 pharmacology   MeSH
• Interleukin-8 pharmacology   MeSH
• Keratin-10 metabolism   MeSH
• Keratin-14 metabolism   MeSH
• Keratinocytes cytology   drug effects   metabolism   MeSH
• Middle Aged MeSH
• Humans MeSH
• Melanocytes metabolism   MeSH
• Melanoma metabolism   pathology   MeSH
• Neoplasm Metastasis MeSH
• Cell Communication * MeSH
• Cell Line, Tumor MeSH
• S100 Proteins metabolism   MeSH
• Aged MeSH
• Gene Expression Profiling MeSH
• Vascular Endothelial Growth Factor A pharmacology   MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Chemokine CXCL1 MeSH
• Fibroblast Growth Factor 2 MeSH
• Interleukin-8 MeSH
• Keratin-10 MeSH
• Keratin-14 MeSH
• S100 Proteins MeSH
• Vascular Endothelial Growth Factor A MeSH

The cell/tissue engineering therapy of extensive or chronic skin wounds is a highly topical task of the contemporary medicine. One of possible therapeutic approaches is grafting of in vitro cultured keratinocytes directly to the wound bed, where the cells colonize the wound, proliferate and improve the re-epithelization process. Because the successful cultivation of keratinocytes needs an application of feeder cells, the exclusion of these cells from the cultivation system is highly required. In this study we show a positive influence of 2-ethoxyethyl methacrylate as a component of cultivation support on growth of keratinocytes without feeder cells. Keratinocytes cultured on these surfaces are able to migrate to the model wound bed in vitro, where they form distinct colonies and have a normal differentiation potential.

• MeSH
• Biocompatible Materials chemistry   MeSH
• Cell Culture Techniques MeSH
• Keratinocytes cytology   physiology   MeSH
• Culture Media MeSH
• Cells, Cultured MeSH
• Humans MeSH
• Methacrylates chemistry   MeSH
• Polymers chemistry   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Biocompatible Materials MeSH
• Culture Media MeSH
• Methacrylates MeSH
• Polymers MeSH

Macroporous hydrogels based on 2-hydroxyethyl methacrylate, 2-ethoxyethyl methacrylate and N-(2-hydroxypropyl)methacrylamide, methacrylic acid and [2-(methacryloyloxy)ethyl]trimethylammonium chloride crosslinked with N,O-dimethacryloylhydroxylamine were prepared. Hydrogels were degraded in a buffer of pH 7.4. Completely water-soluble polymers were obtained over time periods ranging from 2 to 40 days. The process of degradation was followed gravimetrically and by optical and electron microscopy. In vivo biological tests with hydrogels based on copolymers of 2-ethoxyethyl methacrylate/N-(2-hydroxypropyl)methacrylamide were performed.

• MeSH
• Biocompatible Materials metabolism   therapeutic use   MeSH
• Hydrogels metabolism   therapeutic use   MeSH
• Hydrolysis MeSH
• Rats MeSH
• Methacrylates metabolism   therapeutic use   MeSH
• Spinal Cord Diseases pathology   therapy   MeSH
• Porosity MeSH
• Rats, Wistar MeSH
• Materials Testing methods   MeSH
• Absorbable Implants * MeSH
• Animals MeSH
• Check Tag
• Rats MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Biocompatible Materials MeSH
• Hydrogels MeSH
• hydroxyethyl methacrylate MeSH Browser
• Methacrylates MeSH