Telomeres-special DNA-protein structures at the ends of linear eukaryotic chromosomes-define the proliferation potential of cells. Extremely short telomeres promote a DNA damage response and cell death to eliminate cells that may have accumulated mutations after multiple divisions. However, telomere elongation is associated with the increased proliferative potential of specific cell types, such as stem and germ cells.
View Article and Find Full Text PDFImmortalization (genetically induced prevention of replicative senescence) is a promising approach to obtain cellular material for cell therapy or for bio-artificial organs aimed at overcoming the problem of donor material shortage. Immortalization is reversed before cells are used in vivo to allow cell differentiation into the mature phenotype and avoid tumorigenic effects of unlimited cell proliferation. However, there is no certainty that the process of de-immortalization is 100% effective and that it does not cause unwanted changes in the cell.
View Article and Find Full Text PDFThe simplification of alveoli leads to various lung pathologies such as bronchopulmonary dysplasia and emphysema. Deep insight into the process of emergence of the secondary septa during development and regeneration after pneumonectomy, and into the contribution of the drivers of alveologenesis and neo-alveolarization is required in an efficient search for therapeutic approaches. In this review, we describe the formation of the gas exchange units of the lung as a multifactorial process, which includes changes in the actomyosin cytoskeleton of alveocytes and myofibroblasts, elastogenesis, retinoic acid signaling, and the contribution of alveolar mesenchymal cells in secondary septation.
View Article and Find Full Text PDFThe recessive form of dystrophic epidermolysis bullosa (RDEB) is a crippling disease caused by impairments in the junctions of the dermis and the basement membrane of the epidermis. Using ectopic expression of hTERT/hTERT + BMI-1 in primary cells, we developed expansible cultures of RDEB fibroblasts and keratinocytes. We showed that they display the properties of their founders, including morphology, contraction ability and expression of the respective specific markers including reduced secretion of type VII collagen (C7).
View Article and Find Full Text PDFThe recessive form of dystrophic epidermolysis bullosa (RDEB) is a debilitating disease caused by impairments in the junctions of the dermis and the basement membrane of the epidermis. Mutations in the COL7A1 gene induce multiple abnormalities, including chronic inflammation and profibrotic changes in the skin. However, the correlations between the specific mutations in COL7A1 and their phenotypic output remain largely unexplored.
View Article and Find Full Text PDFDespite recent advances in bioengineered therapies, wound healing remains a serious clinical problem. In acute full-thickness wounds, it is desirable to replace both the damaged dermis and epidermis in a single procedure. This approach requires appropriate properties of tissue-engineered dressings to support simultaneous regenerative processes in the dermis and epidermis while they are temporally separated in the natural wound healing process.
View Article and Find Full Text PDFBackground: Despite the significant progress in the development of skin equivalents (SEs), the problem of noninvasively assessing the quality of the cell components and the collagen structure of living SEs both before and after transplantation remains. Undoubted preference is given to in vivo methods of noninvasive, label-free monitoring of the state of the SEs. Optical bioimaging methods, such as cross-polarization optical coherence tomography (CP OCT), multiphoton tomography (MPT), and fluorescence lifetime imaging microscopy (FLIM), present particular advantages for the visualization of such SEs.
View Article and Find Full Text PDFPeople with Down syndrome (DS) are at high risk of developing pathology similar to Alzheimer's disease (AD). Modeling of this pathology in vitro may be useful for studying this phenomenon. In this study, we analyzed three different cultures of neural cells carrying trisomy of chromosome 21, which were generated by directed differentiation from induced pluripotent stem cells (iPS cells).
View Article and Find Full Text PDFMouse submandibular salivary gland cells and liver progenitor cells from long-term in vitro cultures with a high proliferation potential were side-by-side compared by methods of immunocytochemistry, quantitative real-time PCR, flow cytometry, and transcriptome analysis. The two cell types were found to be similar in expressing cell markers such as EpCAM, CD29, c-Kit, Sca-1, and c-Met. In addition, both cell types expressed cytokeratins 8, 18, and 19, alpha-fetoprotein, and (weakly) albumin.
View Article and Find Full Text PDFThis is a comprehensive review on label retaining cells (LRC) in epidermal development and homeostasis. The precise in vivo identification and location of epidermal stem cells is a crucial issue in cutaneous biology. We discuss here the following problems: (1) Identification and location of LRC in the interfollicular epithelium and hair follicle; (2) The proliferative potential of LRC and their role in cutaneous homeostasis (3); LRC phenomenon and the Immortal Strand Hypothesis, which suggests an alternative mechanism for retention of genetic information; (4) Significance of LRC studies for development of stem cell concept.
View Article and Find Full Text PDFThe ability of dermal papilla (DP) cells to induce hair growth was reported in many studies. However, early stages of hair follicle development and signals that govern this process are poorly understood. Therefore, an in vitro model may be a convenient system to study epithelial-mesenchymal interactions and early stages of epidermal morphogenesis, especially in humans.
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