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Diseases leading to terminal hepatic failure are among the most common causes of death worldwide. Transplant of the whole organ is the only effective method to cure liver failure. Unfortunately, this treatment option is not available universally due to the serious shortage of donors. Thus, alternative methods have been developed that are aimed at prolonging the life of patients, including hepatic cells transplantation and bridging therapy based on hybrid bioartificial liver devices. Parenchymal liver cells are highly differentiated and perform many complex functions, such as detoxification and protein synthesis. Unfortunately, isolated hepatocytes display a rapid decline in viability and liver‐specific functions. A number of methods have been developed to maintain hepatocytes in their highly differentiated state in vitro, amongst them the most promising being 3D growth scaffolds and decellularized tissues or coculture with other cell types required for the heterotypic cell‐cell interactions. Here we present a novel approach to the hepatic cells culture based on the feeder layer cells genetically modified using lentiviral vector to stably produce additional amounts of hepatocyte growth factor and show the positive influence of these coculture conditions on the preservation of the hepatic functions of the liver parenchymal cells' model—C3A cells.  相似文献   
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Cilia are microtubule‐based structures that either transmit information into the cell or move fluid outside of the cell. There are many human diseases that arise from malfunctioning cilia. Although mammalian models provide vital insights into the underlying pathology of these diseases, aquatic organisms such as Xenopus and zebrafish provide valuable tools to help screen and dissect out the underlying causes of these diseases. In this review we focus on recent studies that identify or describe different types of human ciliopathies and outline how aquatic organisms have aided our understanding of these diseases.  相似文献   
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Monocytes exhibit direct and indirect antitumour activities and may be potentially useful for various forms of adoptive cellular immunotherapy of cancer. However, blood is a limited source of them. This study explored whether monocytes can be obtained from bone marrow haematopoietic CD34+ stem cells of colon cancer patients, using previously described protocol of expansion and differentiation to monocytes of cord blood-derived CD34+ haematopoietic progenitors. Data show that in two-step cultures, the yield of cells was increased approximately 200-fold, and among these cells, up to 60 % of CD14+ monocytes were found. They consisted of two subpopulations: CD14++CD16+ and CD14+CD16?, at approximately 1:1 ratio, that differed in HLA-DR expression, being higher on the former. No differences in expression of costimulatory molecules were observed, as CD80 was not detected, while CD86 expression was comparable. These CD14+ monocytes showed the ability to present recall antigens (PPD, Candida albicans) and neoantigens expressed on tumour cells and tumour-derived microvesicles (TMV) to autologous CD3+ T cells isolated from the peripheral blood. Monocytes also efficiently presented the immunodominant HER-2/neu369–377 peptide (KIFGSLAFL), resulting in the generation of specific cytotoxic CD8+ T lymphocytes (CTL). The CD14++CD16+ subset exhibited enhanced cytotoxicity, though nonsignificant, towards tumour cells in vitro. These observations indicate that generation of monocytes from CD34+ stem cells of cancer patients is feasible. To our knowledge, it is the first demonstration of such approach that may open a way to obtain autologous monocytes for alternative forms of adaptive and adoptive cellular immunotherapy of cancer.  相似文献   
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The majority of melanocytes originate from the neural crest cells (NCC) that migrate, spread on the whole embryo’s body to form elements of the nervous system and skeleton, endocrinal glands, muscles and melanocytes. Human melanocytes differentiate mainly from the cranial and trunk NCC. Although melanocyte development has traditionally been associated with the dorsally migrating trunk NCC, there is evidence that a part of melanocytes arise from cells migrating ventrally. The ventral NCC differentiate into neurons and glia of the ganglia or Schwann cells. It has been suggested that the precursors for Schwann cells differentiate into melanocytes. As melanoblasts travel through the dermis, they multiply, follow the process of differentiation and invade the forming human fetal epidermis up to third month. After birth, melanocytes lose the ability to proliferate, except the hair melanocytes that renew during the hair cycle. The localization of neural crest-derived melanocytes in non-cutaneous places e.g. eye (the choroid and stroma of the iris and the ciliary body), ear (cells of the vestibular organ, cochlear stria vascularis), meninges of the brain, heart seems to indicate that repertoire of melanocyte functions is much wider than we expected e.g. the protection of tissues from potentially harmful factors (e.g. free radicals, binding toxins), storage ions, and anti-inflammatory action.  相似文献   
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In this work the formation of lipid droplets (LDs) in human endothelial cells culture in response to the uptake of polyunsaturated fatty acids (PUFAs) was studied. Additionally, an effect of 1‐methylnicotinamide (MNA) on the process of LDs formation was investigated. LDs have been previously described structurally and to some degree biochemically, however neither the precise function of LDs nor the factors responsible for LD induction have been clarified. Lipid droplets, sometimes referred in the literature as lipid bodies are organelles known to regulate neutrophil, eosinophil, or tumor cell functions but their presence and function in the endothelium is largely unexplored. 3D linear Raman spectroscopy was used to study LDs formation in vitro in a single endothelial cell. The method provides information about distribution and size of LDs as well as their composition. The incubation of endothelial cells with various PUFAs resulted in formation of LDs. As a complementary method for LDs identification a fluorescence microscopy was applied. Fluorescence measurements confirmed the Raman results suggesting endothelial cells uptake of PUFAs and subsequent LDs formation in the cytoplasm of the endothelium. Furthermore, MNA seem to potentiate intracellular uptake of PUFAs to the endothelium that may bear physiological and pharmacological significance.

Confocal Raman imaging of HAoEC cell with LDs.  相似文献   

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The aim of the study was the assessment of the ability of short peptides to form aggregates under physiological conditions. The dipeptides studied were derived from different aromatic amino acids (heteroaromatic peptides). Tripeptides were obtained from two distinct aromatic amino acids and cysteine or methionine residue in the C‐terminal, N‐terminal, or central position. The ability of the peptides to form fibrous aggregates under physiological conditions was evaluated using three independent methods: the Congo Red assay, the Thioflavin T assay, and microscopic examinations using normal and polarized light. Materials potentially useful for regenerative medicine were selected based on their cytotoxicity to the endothelial cell line EA.hy 926 and physicochemical properties of films formed by peptides. The required parameters of biocompatibility were fulfilled by H?PheCysTrp?OH, H?PheCysTyr?OH, H?PheTyrMet?OH, and H?TrpTyr?OH.  相似文献   
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