Loading...
  • lineage
  • Adult animals consist of many organized differentiated tissues and cell types that are basal to the Bilaterian lineage. (biologists.org)
  • Our hypothesis is that the luminal cell compartment is more complex than initially described, and that an understanding of the developmental relationships within this lineage will help in understanding the cellular context in which breast tumours occur. (biomedcentral.com)
  • Terminally differentiated cells of the B cell lineage that secrete large amounts of antibodies. (amazonaws.com)
  • The further specialized a cell is, the more differentiated it is and as a result it is considered to be more committed to a certain cellular lineage. (wikipedia.org)
  • The mammalian epigenome undergoes global remodeling during early stem cell development that requires commitment of cells to be restricted to the desired lineage. (wikipedia.org)
  • There has been multiple evidence suggesting that the maintenance of the lineage commitment of stem cells are controlled by epigenetic mechanisms such as DNA methylation, histone modifications and regulation of ATP-dependent remolding of chromatin structure. (wikipedia.org)
  • A Neuronal lineage marker is an endogenous tag that is expressed in different cells along neurogenesis and differentiated cells such as neurons. (wikipedia.org)
  • A neuronal lineage marker can be either DNA, mRNA or RNA expressed in a cell of interest. (wikipedia.org)
  • proliferative
  • A population's "growth fraction" - or the fraction of the population that was growing - was actively proliferating, but other cells existed in a non-proliferative state. (wikipedia.org)
  • The proliferative potential of the two groups was unequal and correlated with the cells' location (central or border). (wikipedia.org)
  • spermatogonia
  • PGCs migrate into the developing gonad and become gonadal germ stem cells, oogonia in the ovary and spermatogonia in the testis [ 1 ]. (ijbs.com)
  • A Dark (Ad) and A Pale (Ap) Ad spermatogonia are reserve stem cells. (wikipedia.org)
  • Ap spermatogonia are actively dividing to maintain the stem cell pool. (wikipedia.org)
  • B1-B4 spermatogonia encompass the differentiating spermatogonia and are no longer considered to be stem cells. (wikipedia.org)
  • In mice A Single (As) spermatogonia are capable of creating 2 separate daughter SSCs when they divide or the daughter cells can join and form A Paired (Apr) spermatogonia. (wikipedia.org)
  • Spermatogonia stem cells in mammals are found between the basal membrane of the seminiferous tubules and the Sertoli cells. (wikipedia.org)
  • These A1 spermatogonia undergo a further five divisions to produce A2, A3, A4, intermediate and type B spermatogonia, which can enter meiosis I. It takes around 64 days to produce mature spermatozoa from differentiating SSCs, and 100 million spermatozoa can be produced each day. (wikipedia.org)
  • The stem cells involved are called spermatogonia and are a specific type of stem cell known as gametogonia. (wikipedia.org)
  • Three functionally separate spermatogonial cell types are recognised on the basis of the appearance of the nuclei: type A dark spermatogonia (Ad), type A pale spermatogonia (Ap), and type B spermatogonia (B). The population of spermatogonia is maintained by type Ad spermatogonia. (wikipedia.org)
  • Type Ap spermatogonia repeatedly divide mitotically to produce identical cell clones linked by cytoplasmic bridges. (wikipedia.org)
  • quiescent
  • Moreover, they can make this transition even in the absence of noticeable injuries and are capable of replenishing entire gastric units, in essence serving as quiescent "reserve" stem cells. (wikipedia.org)
  • Quiescence refers to a reversible G0 state where subpopulations of cells reside in a 'quiescent' state before entering the cell cycle after activation in response to extrinsic signals. (wikipedia.org)
  • Hepatocytes are typically quiescent in normal livers but undergo limited replication (less than 2 cell divisions) during liver regeneration after partial hepatectomy. (wikipedia.org)
  • plasticity
  • This phenomenon is referred to as stem cell transdifferentiation or plasticity. (wikipedia.org)
  • There is yet no consensus among biologists on the prevalence and physiological and therapeutic relevance of stem cell plasticity. (wikipedia.org)
  • In fish, the sexual bipotentiality or plasticity of germ stem cells has been demonstrated by transplantation experiments [ 7 ]. (ijbs.com)
  • Subsequent experimentation revealed the plasticity of marrow cells and how their fate is determined by environmental cues. (wikipedia.org)
  • They examined cancer stem cell plasticity in which cancer stem cells can transition between non-cancer stem cells (Non-CSC) and CSC via in situ supporting a more Stochastic model. (wikipedia.org)
  • epithelial cells
  • The ER + luminal progenitors are unique in regard to cell survival, as they are relatively insensitive to loss of oestrogen and progesterone when compared with the other types of mammary epithelial cells. (biomedcentral.com)
  • Differentiated airway epithelial cells can revert into stable and functional stem cells in vivo. (wikipedia.org)
  • Epithelial cells are continuously renewed every 4-5 days through a process of renewal and migration. (wikipedia.org)
  • The brush border on the apical surface of the epithelial cells is covered with glycocalyx, which is composed of oligosaccharides attached to membrane glycoproteins and glycolipids. (wikipedia.org)
  • Throughout the digestive tract, the distribution of the different types of epithelial cells varies according to the function of that region. (wikipedia.org)
  • Regulation
  • Regulation of cancer stem cell self-renewal pathway - There are different pathways involved in the self-renewal of cancer stem cells. (fourwinds10.com)
  • This work demonstrates the ability to gain new insights into the etiology of disease as well as the ability to identify new potential therapeutic approaches by studying the regulation of stem cell function. (hhmi.org)
  • The most important somatic cells that support regulation of SSCs are Sertoli cells. (wikipedia.org)
  • Cells present in the testes express molecules that play key roles in the regulation of SSC self-renewal. (wikipedia.org)
  • Fibroblast growth factor (FGF2) is another molecule crucial for the regulation of stem cell renewal and is expressed in Sertoli cells, Leydig cells and germ cells. (wikipedia.org)
  • Chemokine (C-X-C motif) ligand 12 (CXCL12) signaling via its receptor C-X-C chemokine receptor type 4 (CXCR4) is also involved in regulation of SSC fate decisions.CXCL12 is found in Sertoli cells in the basement membrane of the seminiferous tubules in adult mouse testes, and its receptor is expressed in undifferentiated spermatogonial cells. (wikipedia.org)
  • mechanisms
  • Sean Morrison's laboratory studies the mechanisms that regulate stem cell self-renewal in the hematopoietic and nervous systems and the role these mechanisms play in cancer. (hhmi.org)
  • Cancers arise from the inappropriate or ectopic activation of these self-renewal mechanisms. (hhmi.org)
  • Our studies suggest that cancers arise from the inappropriate or ectopic activation of these self-renewal mechanisms, and therefore, that the mechanisms that are competent to cause cancer also change with age. (hhmi.org)
  • In principle, there are two mechanisms by which distinct properties may be conferred on the daughters of a dividing cell. (wikipedia.org)
  • Histones keep the DNA of the eukaryotic cell tightly packaged through charge interactions between the positive charge on the histone tail and the negative charge of the DNA, as well as between histone tails of nearby nucleosomes.While there are many different types of Histone modifications, in neural epigenetics there are two primary mechanisms which have been explored: histone methylation and histone acetylation. (wikipedia.org)
  • MicroRNAs are a small form of non-coding RNA (ncRNA) which often act as "fine-tuning" mechanisms for gene expression by repressing or inducing messenger RNA (mRNA) in neural cells but can also act directly with transcription factors to guide neurogenesis. (wikipedia.org)
  • Neural Stem Cells generate the cortex in a precise "inside out" manner with carefully controlled timing mechanisms. (wikipedia.org)
  • fate
  • Our data support the view that miR-34 may be involved in pancreatic cancer stem cell self-renewal, potentially via the direct modulation of downstream targets Bcl-2 and Notch, implying that miR-34 may play an important role in pancreatic cancer stem cell self-renewal and/or cell fate determination. (plos.org)
  • Stem-cell niche refers to a microenvironment, within the specific anatomic location where stem cells are found, which interacts with stem cells to regulate cell fate. (wikipedia.org)
  • By continuous intravital imaging in mice, researchers were able to explore the structure of the stem cell niche and to obtain the fate of individual stem cells (SCs) and their progeny over time in vivo. (wikipedia.org)
  • The mitotic spindle must be oriented correctly to ensure that the proper cell fate determinants are distributed appropriately to the daughter cells. (wikipedia.org)
  • Embryonic stem cells are capable of self-renewing and differentiating to the desired fate depending on its position within the body. (wikipedia.org)
  • Based on the histone code hypothesis, distinct covalent histone modifications can lead to functionally distinct chromatin structures that influence the fate of the cell. (wikipedia.org)
  • thus
  • An understanding of the properties of the normal mammary epithelial cell hierarchy will thus be important in understanding the cellular context in which human breast tumours occur. (biomedcentral.com)
  • Thus, the vasa RNA identifies both female and male germ cells in the Asian seabass, and its expression and distribution delineate critical stages of gametogenesis. (ijbs.com)
  • Thus, we study the self-renewal of normal stem cells and the self-replication of developmentally related cancers to understand the physiological function of self-renewal and the ways in which ectopic activation can promote tumorigenesis. (hhmi.org)
  • To securely contain of the contents of the intestinal lumen, the cells of the epithelial layer are joined together by tight junctions thus forming a contiguous and relatively impermeable membrane. (wikipedia.org)
  • Thus, transition into GAlert has been proposed as an adaptive response that enables stem cells to rapidly respond to injury or stress by priming them for cell cycle entry. (wikipedia.org)
  • If a cell retains DNA damage, transcription of a gene can be prevented and thus translation into a protein will also be blocked. (wikipedia.org)
  • On the other hand, in rapidly dividing cells, unrepaired DNA damages that do not kill the cell by blocking replication will tend to cause replication errors and thus mutation. (wikipedia.org)
  • regenerative
  • it is the largest stem cell and regenerative medicine facility in North America. (wikipedia.org)
  • This functional heterogeneity among cancer cells has led to the creation of multiple propagation models to account for heterogeneity and differences in tumor-regenerative capacity: the cancer stem cell (CSC) and stochastic model. (wikipedia.org)
  • transplantation
  • These cells could constitute an unlimited supply of diverse cell types that can be used for cell transplantation or drug discovery. (lu.se)
  • Successful stem cell transplantation was achieved in mice without irradiation after 3 weeks on a valine restricted diet. (wikipedia.org)
  • neuronal cell
  • Although immunohistochemistry is the staple methodology for identifying neuronal cell types, since it is relatively low in cost and a wide range of immunohistochemical markers are available to help distinguish the phenotype of cells in the brain, sometimes it is time-consuming to produce a good antibody. (wikipedia.org)
  • regulate
  • TGFβ The TGFβ family of cytokines regulate the stemness of both normal and cancer stem cells. (wikipedia.org)
  • Osteoblasts (expressing M-CSF, RANKL, and OPG and producing IL-7) may regulate lymphoid (expressing IL-7R) and osteoclast (derived from monocytes, expressing the M-CSF ligand c-Fms and RANK) cell development. (jci.org)
  • Current work in the lab includes the identification of new growth factors that regulate stem cell function and the characterization of aspects of cellular physiology that have not previously been studied in stem cells. (hhmi.org)
  • Several factors are important to regulate stem-cell characteristics within the niche: cell-cell interactions between stem cells, as well as interactions between stem cells and neighbouring differentiated cells, interactions between stem cells and adhesion molecules, extracellular matrix components, the oxygen tension, growth factors, cytokines, and the physicochemical nature of the environment including the pH, ionic strength (e.g. (wikipedia.org)
  • tumors
  • Unlike conventional cancer models used in previous studies, the cancer stem cell model suggests that only a small population of cancer cells drive the initiation, maintenance, and growth of tumors. (fourwinds10.com)
  • Therefore, in this model, cancer stem cells that are not killed by treatments lead to the formation of more invasive and treatment-resistant tumors. (fourwinds10.com)
  • Otherwise, these cancer stem cells will pave the way for the formation of more invasive and treatment-resistant tumors. (fourwinds10.com)
  • Notably, a subpopulation of cancer cells that are often resistant to conventional treatment regimens and are responsible for the initiation of tumors in xenograft models have recently been discovered and characterized. (aacrjournals.org)
  • Cancer stem cells (CSCs) are cancer cells (found within tumors or hematological cancers) that possess characteristics associated with normal stem cells, specifically the ability to give rise to all cell types found in a particular cancer sample. (wikipedia.org)
  • The cancer stem cell model, also known as the Hierarchical Model proposes that tumors are hierarchically organized (CSCs lying at the apex (Fig. 3). (wikipedia.org)
  • pathway
  • Among the target proteins regulated by miR-34 are Notch pathway proteins and Bcl-2, suggesting the possibility of a role for miR-34 in the maintenance and survival of cancer stem cells. (plos.org)
  • Progenitor stem cells are committed to differentiating along a particular cell developmental pathway. (wikipedia.org)
  • stromal
  • HSCs interact not only with osteoblasts but also with other stromal cells, including endothelial cells. (jci.org)
  • HSCs and their progeny are surrounded by stromal cells in BM (Figure 1 ). (jci.org)
  • In this assay system, stromal cells were referred to as colony-forming unit-fibroblasts (CFU-f). (wikipedia.org)
  • Mammalian
  • The SSC niche is found in the seminiferous epithelium of mammalian testis, and is primarily constituted of Sertoli and peritubular myoid cells. (wikipedia.org)
  • For mammalian cells, the maintenance of cytosine methylation is catalyzed by DNA methyltransferases and any disruption to these methyltransferases will cause a lethal phenotype to the embryo. (wikipedia.org)
  • findings
  • Research into stem cells grew out of findings by Ernest A. McCulloch and James E. Till at the University of Toronto in the 1960s. (wikipedia.org)
  • Taken together, these findings identify a previously unrecognized role of TERT in improving the immunomodulatory capacity of BMMSCs, suggesting that aspirin treatment is a practical approach to significantly reduce cell dosage in BMMSC-based immunotherapies. (wiley.com)
  • In 1924, Russian-born morphologist Alexander A. Maximow used extensive histological findings to identify a singular type of precursor cell within mesenchyme that develops into different types of blood cells. (wikipedia.org)
  • precursor
  • myc2 but not myc1 is activated in cycling precursor cells during early oogenesis and spermatogenesis, suggesting that the Hydra Myc2 protein has a possible non-redundant function in cell cycle progression. (biologists.org)
  • One SSC is the precursor for multiple spermatozoa and therefore SSCs are much less numerous in the testes than cells undergoing spermatogenesis. (wikipedia.org)
  • In one, the daughter cells are initially equivalent but a difference is induced by signaling between the cells, from surrounding cells, or from the precursor cell. (wikipedia.org)
  • populations
  • GSCs exist atop a stem cell hierarchy and generate heterogeneous populations that participate in tumor propagation, drug resistance, and relapse. (springer.com)
  • Gene expression profiles were also obtained for all the purified cell populations and correlated to those obtained from breast tumours. (biomedcentral.com)
  • Parent-progeny relationship experiments demonstrated that all luminal progenitor populations in both species are highly plastic and, at low frequencies, can generate progeny representing all mammary cell types. (biomedcentral.com)
  • cellular
  • An understanding of these cells will be essential for understanding the origins and the cellular context of human breast tumours. (biomedcentral.com)
  • The researchers were able to identify the minimal conditions and factors that would be sufficient for starting the cascade of molecular and cellular processes to instruct pluripotent cells to organize the embryo. (wikipedia.org)
  • The G0 phase describes a cellular state outside of the replicative cell cycle. (wikipedia.org)
  • While senescent cells can no longer replicate, they remain able to perform many normal cellular functions. (wikipedia.org)
  • In contrast to cellular senescence, quiescence is not a reactive event but part of the core programming of several different cell types. (wikipedia.org)
  • It was also shown that the two SC compartments acted in accord to maintain a constant cell population and a steady cellular turnover. (wikipedia.org)
  • clonal
  • Scientists Ernest A. McCulloch and James E. Till first revealed the clonal nature of marrow cells in the 1960s. (wikipedia.org)
  • The clonal evolution model, which occurs in both the CSC model and stochastic model, postulates that mutant tumor cells with a growth advantage outproliferate others. (wikipedia.org)
  • These two models are not mutually exclusive, as CSCs themselves undergo clonal evolution. (wikipedia.org)
  • secrete
  • Goblet cells secrete the mucus layer that protects the epitheilium from the lumenal contents. (wikipedia.org)
  • Enteroendocrine cells secrete various gastrointestinal hormones including secretin, pancreozymin, enteroglucagon among others. (wikipedia.org)
  • generate
  • A variety of nontumorigenic stem cells display the ability to generate multiple cell types. (wikipedia.org)
  • The theory suggests that conventional chemotherapies kill differentiated or differentiating cells, which form the bulk of the tumor but do not generate new cells. (wikipedia.org)