It is primarily important to define the standard features and factors that affect dental pulp stem cells (DPSCs) for their broader use in tissue engineering. This study aimed to verify whether DPSCs isolated from various teeth extracted from the same donor exhibit intra-individual variability and what the consequences are for their differentiation potential. The heterogeneity determination was based on studying the proliferative capacity, viability, expression of phenotypic markers, and relative length of telomere chromosomes. The study included 14 teeth (6 molars and 8 premolars) from six different individuals ages 12 to 16. We did not observe any significant intra-individual variability in DPSC size, proliferation rate, viability, or relative telomere length change within lineages isolated from different teeth but the same donor. The minor non-significant variances in phenotype were probably mainly because DPSC cell lines comprised heterogeneous groups of undifferentiated cells independent of the donor. The other variances were seen in DPSC lineages isolated from the same donor, but the teeth were in different stages of root development. We also did not observe any changes in the ability of cells to differentiate into mature cell lines-chondrocytes, osteocytes, and adipocytes. This study is the first to analyze the heterogeneity of DPSC dependent on a donor.
- Klíčová slova
- dental stem cells, intra-individual variability, mesenchymal stem cells, regenerative medicine, same donor isolation, stem cell characterization,
- MeSH
- buněčná diferenciace fyziologie MeSH
- buněčné linie MeSH
- buněčný rodokmen fyziologie MeSH
- chondrocyty fyziologie MeSH
- dárci tkání MeSH
- individuální biologická variabilita MeSH
- kmenové buňky fyziologie MeSH
- lidé MeSH
- mladiství MeSH
- osteocyty fyziologie MeSH
- proliferace buněk fyziologie MeSH
- tukové buňky fyziologie MeSH
- zubní dřeň fyziologie MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
Melanocytes are pigmented cells residing mostly in the skin and hair follicles of vertebrates, where they contribute to colouration and protection against UV-B radiation. However, the spectrum of their functions reaches far beyond that. For instance, these pigment-producing cells are found inside the inner ear, where they contribute to the hearing function, and in the heart, where they are involved in the electrical conductivity and support the stiffness of cardiac valves. The embryonic origin of such extracutaneous melanocytes is not clear. We took advantage of lineage-tracing experiments combined with 3D visualizations and gene knockout strategies to address this long-standing question. We revealed that Schwann cell precursors are recruited from the local innervation during embryonic development and give rise to extracutaneous melanocytes in the heart, brain meninges, inner ear, and other locations. In embryos with a knockout of the EdnrB receptor, a condition imitating Waardenburg syndrome, we observed only nerve-associated melanoblasts, which failed to detach from the nerves and to enter the inner ear. Finally, we looked into the evolutionary aspects of extracutaneous melanocytes and found that pigment cells are associated mainly with nerves and blood vessels in amphibians and fish. This new knowledge of the nerve-dependent origin of extracutaneous pigment cells might be directly relevant to the formation of extracutaneous melanoma in humans.
- Klíčová slova
- Endothelin 3 and endothelin receptor B, Extracutaneous pigment cell, Glial precursor, Hypopigmentation-associated deafness, Peripheral nerves, Targeted recruitment,
- MeSH
- buněčný rodokmen fyziologie MeSH
- embryonální vývoj fyziologie MeSH
- melanocyty metabolismus fyziologie MeSH
- meningy metabolismus fyziologie MeSH
- mozek metabolismus fyziologie MeSH
- myši MeSH
- nervový systém metabolismus patofyziologie MeSH
- obojživelníci metabolismus fyziologie MeSH
- receptor endotelinu B metabolismus MeSH
- ryby metabolismus fyziologie MeSH
- Schwannovy buňky metabolismus fyziologie MeSH
- srdce fyziologie MeSH
- těhotenství MeSH
- vnitřní ucho metabolismus fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- receptor endotelinu B MeSH
The present study was undertaken to estimate the approximate size of nuclear regions occupied by nucleolar bodies during the cell differentiation and maturation. The differentiation and maturation of human leukemic granulocytic cells in patients suffering from the chronic phase of the chronic granulocytic leukemia (CML) represented a convenient model for such study because of the large number of cells for the diameter measurements at the single cell level. Early and advanced differentiation or maturation stages of these cells are well defined and nucleolar bodies and nuclear outlines are easily seen by simple cytochemical methods for the visualization of RNA and silver stained proteins in smear preparations. During the cell differentiation and maturation, the estimated size of the nuclear region occupied by nucleolar bodies decreased in both untreated and treated patients with the anti-leukemic therapy. However, the size reduction of nucleolar bodies in differentiated and mature cells was larger than that of the nucleus. In addition, the results also indicated that the nuclear region occupied by nucleolar bodies was characteristic for each differentiation and maturation stage of the granulocytic cell lineage and was not substantially influenced by the anti-leukemic therapy of CML patients.
- MeSH
- buněčná diferenciace fyziologie MeSH
- buněčné jadérko fyziologie MeSH
- buněčný rodokmen fyziologie MeSH
- chronická myeloidní leukemie patologie MeSH
- granulocyty fyziologie MeSH
- lidé MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
The sine oculis homeobox 1 (Six1) gene encodes an evolutionarily conserved transcription factor. In the past two decades, much research has indicated that Six1 is a powerful regulator participating in skeletal muscle development. In this review, we summarized the discovery and structural characteristics of Six1 gene, and discussed the functional roles and molecular mechanisms of Six1 in myogenesis and in the formation of skeletal muscle fibers. Finally, we proposed areas of future interest for understanding Six1 gene function.
- Klíčová slova
- Molecular mechanism., Muscle, Muscle fiber, Muscle progenitors, Regulatory network, Six1,
- MeSH
- buněčný rodokmen genetika fyziologie MeSH
- druhová specificita MeSH
- homeodoménové proteiny genetika metabolismus MeSH
- kosterní svaly růst a vývoj metabolismus MeSH
- regulace genové exprese fyziologie MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- homeodoménové proteiny MeSH
The divergence of two differentiating extraembryonic cell types (trophectoderm and primitive endoderm) from the pluripotent epiblast population (the source of fetal progenitor cells) by the blastocyst stage of mouse development relies upon the activation and execution of lineage-specific gene expression programmes. While our understanding of the central transcription factor 'effectors' directing these cell-fate choices has accumulated rapidly, what is less clear is how the differential expression of such genes within the diverging lineages is initially generated. This review summarizes and consolidates current understanding. I introduce the traditional concept and importance of a cell's spatial location within the embryo, referencing recent mechanistic and molecular insights relating to cell fate. Additionally, I address the growing body of evidence that suggests that heterogeneities among blastomeres precede, and possibly inform, their spatial segregation in the embryo. I also discuss whether the origins of such early heterogeneity are stochastic and/or indicative of intrinsic properties of the embryo. Lastly, I argue that the robustness and regulative capacity of preimplantation embryonic development may reflect the existence of multiple converging, if not wholly redundant, mechanisms that act together to generate the necessary diversity of inter-cell-lineage gene expression patterns.
- Klíčová slova
- cell fate, preimplantation embryo, probabilistic, regulative development, stochastic, transcription,
- MeSH
- blastomery fyziologie MeSH
- buněčná diferenciace fyziologie MeSH
- buněčný rodokmen fyziologie MeSH
- embryo savčí metabolismus fyziologie MeSH
- embryonální vývoj fyziologie MeSH
- myši MeSH
- pohyb buněk fyziologie MeSH
- transkripční faktory metabolismus MeSH
- vývojová regulace genové exprese fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
- Názvy látek
- transkripční faktory MeSH
Adult stem cells have been intensively studied for their potential use in cell therapies for neurodegenerative diseases, ischemia and traumatic injuries. One of the most promising cell sources for autologous cell transplantation is bone marrow, containing a heterogenous cell population that can be roughly divided into hematopoietic stem and progenitor cells and mesenchymal stem cells (MSCs). MSCs are multipotent progenitor cells that, in the case of severe tissue ischemia or damage, can be attracted to the lesion site, where they can secrete bioactive molecules, either naturally or through genetic engineering. They can also serve as vehicles for delivering therapeutic agents. Mobilized from the marrow, sorted or expanded in culture, MSCs can be delivered to the damaged site by direct or systemic application. In addition, MSCs can be labeled with superparamagnetic nanoparticles that allow in vivo cell imaging. Magnetic resonance imaging (MRI) is thus a suitable method for in vivo cell tracking of transplanted cells in the host organism. This review will focus on cell labeling for MRI and the use of MSCs in experimental and clinical studies for the treatment of brain and spinal cord injuries.
- MeSH
- barvení a značení metody trendy MeSH
- buněčná diferenciace fyziologie MeSH
- buněčný rodokmen fyziologie MeSH
- centrální nervový systém cytologie fyziologie MeSH
- lidé MeSH
- magnetická rezonanční tomografie metody trendy MeSH
- mezenchymální kmenové buňky cytologie fyziologie MeSH
- nanočástice normy MeSH
- pohyb buněk fyziologie MeSH
- transplantace mezenchymálních kmenových buněk metody trendy MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- přehledy MeSH
Neural progenitors of the mouse forebrain can be propagated in vitro as neurospheres in the presence of bFGF and EGF. However, less is understood whether regional characteristics or developmental stage properties of these cells are maintained in neurosphere cultures. Here we show that the original cell fate is lost in neurosphere cultures. We isolated neural progenitors from the dorsal telencephalon of D6-GFP mice and cultured them in vitro. The expression profile was specifically changed in cultured cells in just three passages. Markers of the dorsal forebrain were downregulated and several ventrally-expressed genes were induced. The altered gene expression led to a profound phenotypic change of cultured cells. D6-GFP positive cortical progenitors produce excitatory neurons in the cortex and few astrocytes in vivo but after culture in vitro, these cells differentiate into many astrocytes and also oligodendrocytes and inhibitory neurons. Wnt signaling in cultured neurospheres was downregulated in the same manner as other dorsal markers but dominant active Wnt signaling slowed down the loss of the dorsal identity in neurospheres.
- MeSH
- astrocyty cytologie metabolismus MeSH
- buněčná diferenciace fyziologie MeSH
- buněčné sféroidy cytologie MeSH
- buněčný rodokmen fyziologie MeSH
- genetické markery genetika MeSH
- interneurony cytologie metabolismus MeSH
- kmenové buňky cytologie metabolismus MeSH
- mozková kůra cytologie embryologie metabolismus MeSH
- myši transgenní MeSH
- myši MeSH
- neuroglie cytologie metabolismus MeSH
- neurony cytologie metabolismus MeSH
- oligodendroglie cytologie metabolismus MeSH
- promotorové oblasti (genetika) genetika MeSH
- rekombinantní fúzní proteiny genetika MeSH
- telencefalon cytologie embryologie metabolismus MeSH
- vývojová regulace genové exprese genetika MeSH
- zelené fluorescenční proteiny genetika MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- genetické markery MeSH
- rekombinantní fúzní proteiny MeSH
- zelené fluorescenční proteiny MeSH
Human early erythroid precursors classified according to the nuclear size were studied to provide information on nucleoli in these cells using simple cytochemical procedures for demonstration of RNA and proteins of silver-stained nucleolar organizers. K2 cells with nuclear diameter larger than 13 microm and K1 cells with nuclear diameter larger than 9 microm corresponding to proerythroblasts and macroblasts (large basophilic erythroblasts) mostly possessed large irregularly shaped nucleoli with multiple fibrillar centres representing "active nucleoli". K1/2 cells with nuclear diameter smaller than 9 microm corresponding to small basophilic erythroblasts were usually characterized by the presence of micronucleoli representing "inactive nucleolar types". On the other hand, a few K1/2 cells contained large nucleoli with multiple fibrillar centres similar to those present in K2 cells and thus appeared as "microproerythroblasts". The nucleolar asynchrony expressed by the presence of large irregularly shaped nucleoli with multiple nucleoli (active nucleoli) and ring-shaped nucleoli (resting nucleoli) in one and the same nucleus of K2 or K1 cells was not exceptional and might reflect a larger resistance of these cells to negative factors influencing the erythropoiesis. The intranucleolar translocation of silver-stained nucleolus organized regions was noted in K2 cells and might indicate the premature aging of these cells without further differentiation. More studies, however, are required in this direction.
- MeSH
- barvení stříbrem MeSH
- buněčná diferenciace fyziologie MeSH
- buněčné jadérko fyziologie ultrastruktura MeSH
- buněčné jádro fyziologie ultrastruktura MeSH
- buněčný rodokmen fyziologie MeSH
- erytroblasty klasifikace cytologie fyziologie MeSH
- erytrocyty cytologie fyziologie MeSH
- erytropoéza fyziologie MeSH
- jaderné proteiny metabolismus MeSH
- lidé MeSH
- transport proteinů fyziologie MeSH
- tvar buňky fyziologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- jaderné proteiny MeSH
A number of surprising observations have shown that stem cells, in suitable conditions, have the ability to produce a whole spectrum of cell types, regardless, whether these tissues are derived from the same germ layer or not. This phenomenon is called stem cell plasticity, which means that tissue-specific stem cells are mutually interchangeable. In our experiments, as a model, we used neural stem cells (NSCs) harvested from fetal (E14-15) neocortex and beta-galactosidase positive. In the first experiment we found that on days 12 and 30 after sub-lethal irradiation (LD 8.5 Gy) and (beta-galactosidase(+)) NSCs transplantation all mice survived, just as the group with bone marrow transplantation. Moreover, the bone marrow of mice transplanted NSCs contained the number of CFU-GM colonies with beta-galactosidase(+) cells which was as much as 50% higher. These differences were statistically significant, p<0.001. In the second experiment, we studied kinetics of (beta-galactosidase(+)) NSCs after their transplantation to sub-lethally irradiated mice. Histochemistry of tissues was performed on days 12 and 30 post-transplantation, and beta-galactosidase(+) cells were detected with the help of histochemical examination of removed tissues (lung, liver, spleen, thymus, and skeletal muscle). In tissues removed on day 12 post-transplantation, we found a significantly higher number of beta-galactosidase(+) cells in the spleen and thymus on day 30. While we presumed the presence beta-galactosidase(+) cells in the spleen, as spleen and reticuloendothelial system represent an important retaining system for different cell types, the presence of beta-galactosidase(+) cells in the thymus was rather surprising but very interesting. This indicates a certain mutual and close interconnection of transplanted stem cells and immune system in an adult organism. In the third experiment, we verified the mutual interchange of Sca-1 surface antigen in the bone marrow cells and NSCs before transplantation. Analysis of this antigen showed 24.8% Sca-1 positive cells among the bone marrow cells, while NSCs were Sca-1 negative. Our experiments show that NSCs share hemopoietic identity and may significantly influence the recovery of damaged hematopoiesis but do not have typical superficial markers as HSCs. This result is important for the determination of predictive factors for hemopoiesis recovery, for stem cell plasticity and for their use in the cell therapy.
- MeSH
- buněčný rodokmen fyziologie MeSH
- celotělové ozáření MeSH
- hematopoéza fyziologie MeSH
- kmenové buňky cytologie fyziologie MeSH
- mozek cytologie fyziologie MeSH
- myši inbrední BALB C MeSH
- myši MeSH
- plod cytologie fyziologie MeSH
- transplantace kmenových buněk * MeSH
- transplantační chiméra fyziologie MeSH
- zvířata MeSH
- Check Tag
- myši MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Research Support, N.I.H., Extramural MeSH
- Research Support, U.S. Gov't, P.H.S. MeSH
Fetal liver (FL) becomes a major organ of hematopoiesis at mouse embryonic day (E) 11 and E12, when definitive hematopoietic stem cells, originating from the aorta-gonads-mesonephros region, colonize the hepatic tissue. Unipotent B-cell progenitors are very rare in FL by day 12, whereas erythropoiesis prevails. We have studied hematopoiesis in FL from different gestational ages, with special emphasis on B lymphopoiesis. The mRNA levels of selected liver-specific genes, hematopoietic lineage-specific genes, and genes for selected cytokines/hormones as well as for their receptors were evaluated by real-time polymerase chain reaction in FL from E12.5, E14.5, and E17.5, adult liver and adult bone marrow (BM). The level of B lineage-related gene expression in FL was very low at E12.5. There was also a significantly lower fraction of B220+ and CD19+ B cells in E12.5 FL compared with E17.5 FL. To analyze whether these differences reflect different stem cell potentials occurring during FL development, 10(6) or 5 x 10(6) of FL cells collected from embryos at E12.5 or E17.5 and those from adult BM were transplanted into sublethally irradiated (3- or 6-Gy) congenic mice. Short-term and long-term repopulation of B and T cells and granulocyte/macrophage lineages from donor FL or adult BM cells were evaluated in competition to adult hematopoiesis of sublethally irradiated recipients. In short-term repopulation, the transplantation of E12.5 FL cells resulted in a lower blood chimerism compared with that of E17.5 FL cells. However, the proportion of B lymphopoiesis exerted by E12.5 FL cells was not different from that of E17.5 FL or adult BM. This study demonstrates that E12.5 FL contains hematopoietic stem cells with fully developed B-cell repopulating capacity and that the developmental period of fetal hematopoiesis between E12.5 and E17.5 is not an obligatory phase for the adult B lymphopoiesis.
- MeSH
- B-lymfocyty cytologie fyziologie MeSH
- buněčná diferenciace fyziologie MeSH
- buněčný rodokmen fyziologie MeSH
- gestační stáří MeSH
- hematopoetické kmenové buňky cytologie fyziologie MeSH
- játra cytologie fyziologie MeSH
- lymfopoéza fyziologie MeSH
- myši MeSH
- plod cytologie fyziologie MeSH
- těhotenství MeSH
- transplantace hematopoetických kmenových buněk * MeSH
- zvířata MeSH
- Check Tag
- mužské pohlaví MeSH
- myši MeSH
- těhotenství MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
