Induced pluripotent stem cells (iPSC) are undifferentiated cells capable of unlimited self-renewal. By introducing specific transcription factors, any somatic (fully differentiated) cell of the mammalian body can be changed (reprogrammed) into iPSC. The iPSCs are very similar to embryonic stem cells in their molecular and functional properties. By using specific factors, iPSCs can be differentiated into each of the about 200 cell types in the human body. The big advantage of iPSCs is the availability of somatic cells (isolation from blood or skin biopsy). Creation of "tailor made" iPSCs for each patient would allow transplantation of own cells and avoid problems with finding an immunologically compatible donor. and Kateřina Vodičková Kepková, Petr Vodička, Jan Motlík.
Exocytotic machinery in neuronal and endocrine tissues is sensitive to changes in intracellular Ca2+ concentration. Endocrine cell models, that are most frequently used to study the mechanisms of regulated exocytosis, are pancreatic beta cells, adrenal chromaffin cells and pituitary cells. To reliably study the Ca2+ sensitivity in endocrine cells, accurate and fast determination of Ca2+ dependence in each tested cell is required. With slow photo-release it is possible to induce ramp-like increase in intracellular Ca2+ concentration ([Ca2+]i) that leads to a robust exocytotic activity. Slow increases in the [Ca2+] i revealed exocytotic phases with different Ca2+ sensitivities that have been largely masked in step-like flash photo-release experiments. Strikingly, in the cells of the three described model endocrine tissues (beta, chromaffin and melanotroph cells), distinct Ca2+ sensitivity ‘classes’ of secretory vesicles have been observed: a highly Ca2+ -sensitive, a medium Ca2+ -sensitive and a low Ca2+ - sensitive kinetic phase of secretory vesicle exocytosis. We discuss that a physiological modulation of a cellular activity, e.g. by activating cAMP/PKA transduction pathway, can switch the secretory vesicles between Ca2+ sensitivity classes. This significantly alters late steps in the secretory release of hormones even without utilization of an additional Ca2+ sensor protein., J. Dolenšek, M. Skelin, M. S. Rupnik., and Obsahuje bibliografii a bibliografické odkazy
CARM1 i nteracts with numerous transcription factors to mediate cellular processes, especially gene expression. This is important for the maintenance of ESC pluripotency or intervention to tumorigenesis. Here, we studied epigenomic effects of two potential CARM1 m odulators: an activator (EML159) and an inhibitor (ellagic acid dihydrate, EA). We examined nuclear morphology in human and mouse embryonic stem cells (hESCs, mESCs), as well as in iPS cells. The CARM1 modulators did not function similarly in all cell type s. EA decreased the levels of the pluripotency markers, OCT4 and NANOG, particularly in iPSCs, whereas the levels of these proteins increased after EML159 treatment. EML159 treatment of mouse ESCs led to decreased levels of OCT4 and NANOG, which was accomp anied by an increased level of Endo -A. The same trend was observed for NANOG and Endo -A in hESCs affected by EML159. Interestingly, EA mainly changed epigenetic features of nucleoli because a high level of arginine asymmetric di- methylation in the nucleoli of hESCs was reduced after EA treatment. ChIP -PCR of ribosomal genes confirmed significantly reduced levels of H3R17me2a, in both the promoter region of ribosomal genes and rDNA encoding 28S rRNA, after EA addition. Moreover, EA treatment changed the nuclear pattern of AgNORs (silver -stained nucleolus organizer regions) in all cell types studied. In EA -treated ESCs, AgNOR pattern was similar to the pattern of AgNORs after inhibition of RNA pol I by actinomycin D. Together, inhibitory effect of EA on arginine methylation and effect on related morphological parameters was especially observed in compartment of nucleoli., M. Franek, S. Legartová, J. Suchánková, C. Milite, S. Castellano, G. Sbardella, S. Kozubek, E. Bártová., and Obsahuje bibliografii
Metoda fázově modulační časově rozlišené konfokální mikrospektrofluorimetrie byla využita v kombinaci s fluorescenčním zobrazováním k monitorování transportu fluorescenčně značeného terapeutického oligonukleotidu do buněk za pomoci kationického porfyrinu. Bylo možné sledovat stabilitu vytvořeného transportního komplexu ve vnitrobuněčném prostředí a interakci transportovaného oligonukleotidu s cílovými molekulárními strukturami v buněčném jádře., Time-resolved phase modulation microspectrofluorimetry in combination with fluorescence microscopy imaging have been applied to monitor the cellular uptake fluorescent-labeled therapeutic oligonucleotide delivered by a cationic porphyrin. Transport complex stability inside the cell and the oligonucleotide interaction with the target molecular structures in the cell nucleus has been monitored., Petr Praus, Eva Kočišová, Josef Štěpánek, Peter Mojzeš., and Obsahuje bibliografii
Cell-penetrating compounds are substances that enhance the cellular uptake of various molecular cargoes that do not easily cross the cellular membrane. The majority of cell-penetrating compounds described in the literature are cell-penetrating peptides (CPPs). This review summarizes the various structural types of cell-penetrating compounds, with the main focus on CPPs. The authors present a brief overview of the history of CPPs, discuss the various types of conjugation of CPPs to biologically active cargoes intended for cell internalization, examine the cell-entry mechanisms of CPPs, and report on the applications of CPPs in research and in preclinical and clinical studies., E. Böhmová, D. Machová, M. Pechar, R. Pola, K. Venclíková, O. Janoušková, T. Etrych., and Obsahuje bibliografii
This paper is devoted to yet unpublished electrode-less methods (ELM) of cell layers impedance measurement based on transformer principle. The main advantage of ELM is elimination uncertainties caused by interface between electrodes and measured electrolyte. The method of avoiding distortion caused by non-ideal transformer transfer function (“deconvolution”) and errors caused by residual voltage is described. The modification of original transformer based method allowing to measure an impedance of inserted object is proposed. Results of several calibration measurements confirming the proper function of ELM including example of transepithelial resistance of cells layer are presented. Crucial parts of measuring system and recommendation for their realization are included., J. Krůšek, S. Ďáďo., and Obsahuje bibliografii
Cílená změna původní identity buňky v identitu jinou neboli reprogramování buněk nachází své uplatnění jak v základním výzkumu, tak i v případné buněčné terapii. Z mnoha postupů reprogramování autoři představují přípravu indukovaných pluripotentních buněk (iPS), transdiferencovaných anebo přímo reprogramovaných buněk. Je popsána cesta přípravy a z ní plynoucí vlastnosti a potenciál indukovaných buněk., Induced change in the identity of the cell known as reprogramming of the somatic cell is applicable both in basic research and cell therapy. Out of many reprogramming approaches the authors introduce the derivation of induced pluripotent stem (iPS), transdifferentiated and direct reprogrammed cells. The workflow for the preparation of induced cells and a comment on their properties and potentials are given., and Jiří Klíma, Irena Lišková, Jan Motlík.
Výzkum primárních procesů fotosyntézy probíhá na trojmezí tří velkých přírodních věd: fyziky, chemie a biologie. Předmětem tohoto článku je stručný přehled sledu elementráních chemických a fyzikálních pochodů od záchytu fotonu po syntézu adenosintrifosfátu (ATP) a úvod do kvantové teorie světlosběrných fotosyntetických antén., Research of primary processes of photosynthesis occurs at the boundary of three great natural sciences: physics, chemistry and biology. This article gives a brief overview of the elementary chemical and physical processes from the absorption of a photon to the synthesis of adenosintriphosphate molecules, and it introduces the reader to the theory of photosynthetic light-harvesting antennae., Tomáš Mančal., and Obsahuje bibliografii
Raman microspectroscopy (μRS) and imaging is gradually becoming a practical tool for contactless and nondestructive analysis of microscopis objects. Due to the combination of chemical specificity of vibrational spectra and spatial resolution offered by confocal optical microscopy, μRS techniques are particularly suitable for studying chemical composition and morphology of living cells and biological tissues. Progress in experimental technniques and development of methods making the informational richness of vibrational spectra more accessible allowed expansion of μRS beyond the walls of specialized spectroscopis laboratories directly into biomedical practice., Ramanova mikrospektroskopie (μRS) a zobrazování se postupně prosazuje jako praktický nástroj pro bezkontaktní a nedestruktivní analýzu mikroskopických objektů. Díky kombinaci chemické specificity vibračních spekter a prostorového rozlišení poskytovaného konfokální optickou mikroskopií jsou techniky μRS zvlášť vhodné pro studium chemického složení a morfologie živých buněk i biologických tkání. Pokrok v experimentální technice a rozvoj metod zpřístupňujících informační bohatství vibračních spekter umožnily rozšíření μRS mimo zdi specializovaných spektroskopických laboratoří přímo do biomedicínské praxe., Peter Mojzeš, Jan Palacký, Václava Bauerová, Lucie Bednárová., and Obsahuje bibliografii
Micropatterned surfaces have been used as a tool for controlling the extent and strength of cell adhesion, the direction of cell growth and the spatial distribution of cells. In this study, chemically micropattern ed surfaces were prepared by successive plasma polymerization of acrylic acid (AA) and 1,7-octadiene (OD) through a mask. Rat vascular smooth muscle cells (VSMC), bovine endothelial cells (EC), porcine mesenchymal stem cells (MSC) or human skeletal muscle cells (HSKMC) were seeded on these surfaces in densities from 9,320 cells/cm2 to 31,060 cells/cm2. All cell types adhered and grew preferentially on the strip-like AA domains. Between day 1 and 7 after seeding, the percentage of cells on AA domains ranged from 84.5 to 63.3 % for VSMC, 85.3 to 73.5 % for E, 98.0 to 90.0 % for MSC, and 93.6 to 55.0 % for HSKMC. The enzyme-linked immunosorbent assay (ELISA) revealed that the concentration of alpha-actin per mg of protein was significantly higher in VSMC on AA. Similarly, immunofluorescence staining of von Willebrand factor showed more apparent Weibel-Palade bodies in EC on AA domains. MSC growing on AA had better developed beta-actin cytoskeleton, although they were less stained for hyaluronan receptor (CD44). In accordance with this, MSC on AA contained a higher concentration of beta-actin, although the concentration of CD44 was lower. HSKMC growing on AA had a better developed alpha-actin cytoskeleton. These results based on four cell types suggest that plasma polymerization is a suitable method for producing spatially defined patterned surfaces for controlled cell adhesion, proliferation and maturation., E. Filová ... [et al.]., and Obsahuje seznam literatury