Journal of Stem Cells最新文献

The concept of extramedullary hematopoiesis for production of organ-specific antigen presenting cells has importance in immunity in terms of the compartmentalisation of the immune response in different tissue sites. A new and distinct dendritic-like antigen presenting cell subtype is described which is dependent on the spleen microenvironment for development. Cells arise by a unique developmental pathway distinct from other dendritic cells (DC). In particular, a self-renewing progenitor of these cells has been identified in spleen upstream of the earliest DC progenitor currently identified in bone marrow. This progenitor depends on the splenic microenvironment for maintenance and proliferation, adding further support for spleen as a site for hematopoiesis.

Unlabelled: Wound healing is an inherent property of injured tissue or a group of cells. The healing front is always developed by new cells which are progenitor of differentiated parental cells. In cancer tissues we aim to study the healing front and observed an enriched population of stem cell like properties in the developing front when compared to the other areas of the cell matrix.

Method: In vitro scratch assays with special focus on stem cell expression was used to analyze metastatic potential of the tumor cell, epithelial to mesenchymal transition and rate of cell migration to get an insight into the genes and the proteins getting expressed at the developing front. In this protocol we describe a fluorescence dependent method to document stem cell like enrichment at the developing front of a given wound in drug treated and untreated control cells under the same culture conditions in a time lag manner. We have tried to compare the rate of cell migration and the expression levels of stem cell markers between the treated and untreated cells.

Results: CD44 being a cell surface protein and being involved in cell migration and proliferation, higher intensity of CD44 was observed at the developing front with increasing time. The rate of cell migration differed with different treatments and so did the CD44 expression with expression being higher in 0.6mM concentration of bleomycin when compared to 0.4mM. Similar expression was observed for ALDH1 stem cell marker. This particular technique can not only be used for studying expression of CSC markers (like CD44, ALDH1) but also in assaying the expression profile of several proteins involved in cellular processes like EMT (Epithelial to Mesenchymal Transition), cell migration, tumorigeneisis and rate of proliferation.

Conclusion: Would healing is an integral property of solid tissues and in solid tumors properties of solid tissue wound are important characteristics of tumor development. Therefore combining the properties of stem cell like enrichment in the development front would be an important and fast assay to study migratory and metastatic properties of an invitro culture.

The time lapse photography is not a new method for assessing the dynamics of early embryo development in vitro. It has been used many times in the past for studying cleavages and blastulation of embryos of various animal species. However, this technique became available for routine use in an human in vitro fertilization (IVF) programme only a couple years ago and it becomes more and more popular today. The new time lapse systems are using modified microscopes which are positioned within the incubators. The observation of embryos does not need the opening of incubators. By sequential photographing of each embryo separately with camera of low intensity illumination, more than 1400 pictures of embryo are made. All these pictures are collected together and transformed into a short movie with software. This system offers the observation of dynamics of embryo development. The studies, which have used a time lapse technique for studying embryo development, revealed that the timing between different events can be used for predicting its developmental potential. In this paper the advantages and drawbacks of time lapse photography is precisely described. An overview through the published papers analyzing the dynamics of human embryo development from the zygote toward blastocyst is done and new timing parameters for grading zygotes, early embryos and blastocysts are analyzed.

As described in this book, the interaction between the immune system and the brain can affect multiple cerebral functions, such as: neural remodeling, synaptic plasticity or neurotransmitter releasing. Neurogenic niches are not the exception, in fact, pro-inflammatory cytokines and chemokines exert a strong regulation in neural stem cells (NSCs) of the ventricular-subventricular zone (V-SVZ) by interacting with cell membrane receptors and activating multiple downstream pathways. These neuro-immune interactions modulate quiescence, cell adhesion, migration, self-renewal, differentiation, cytoskeletal rearrangement, and cell survival. In this chapter, we describe the cellular composition and cytoarchitecture of the main neurogenic niche in the adult mammalian brain: the V-SVZ. We also discuss the current evidence indicating that many immunological molecules can control the function of this neurogenic niche in the adult brain under both physiological and pathological conditions.

Nearly 2 million people annually die prematurely from various illness contributed by indoor air pollutants (IAP). Such pollutants affect the lungs leading to diseases ranging from bronchial diseases to malignant lung cancer. Stem cells (SC) with the property of self-renewal, pluripotency, and capability of homing into tumors and metastases, have been reported to be promising in treatment of lung cancer. In this review, we have tried to understand the role of components of IAP affect the SC. Although very few studies have been conducted in these lines, existing reports suggest that IAP causes damage to stem cells and their niches thereby reducing successful chances of autologous stem cell transplantation and therapy. The mechanism by which components of IAP affects the functioning of stem cells thus conferring toxicity remains unexplored. The future scope of this review lies in revealing answer to underlying questions of repair and modulation of stem cells in therapeutic treatment of lung diseases.

The aim of this study was to evaluate human adipose-derived stem cells (ASCs) from passage 2 (P2) to P8 cultured in medium containing 5% autologous serum (AS) after a long-term cryopreservation with regards to their surface marker expression, differentiation potential, and immunosuppressive effect in vitro. 8-color flow cytometry and real time PCR were used to determine mesenchymal stem cell (MSC) surface marker expression on ASCs from various passages. In vitro differentiation ability and immunomodulatory properties of ASCs were also tested. Flow cytometry showed that all ASCs express typical MSC markers CD29, CD44, CD73, CD90, CD105 simultaneously, but do not express such markers as HLA-DR, CD34, CD14, CD19, and CD45. Furthermore, median fluorescence intensity of positive cell surface markers increased with each subsequent passage indicating the accumulation of protein expression. The multilineage differentiation demonstrated the ability of ASCs from P6 to efficiently differentiate into adipocytes and chondrocytes, but their potential of osteogenic differentiation was diminished. Data from co-culture of ASCs and autologous peripheral blood mononuclear cells (PBMNCs) indicated that ASCs from P3, P6, and P9 significantly reduce the proliferation of PBMNCs at ASCs:PBMNCs ratio 1:1 and this suppression is dose dependent. This study demonstrated that ASCs from P2 to P8, cultured in the presence of AS, represent a highly homogeneous cell population with a peak accumulation of MSC surface proteins at P5 possessing multilineage differentiation ability and significant immunosuppressive properties after double freezing and more than 4 years of cryopreservation.

Endothelial Progenitor Cells (EPCs) are bone-marrow derived stem cells that are postulated to contribute to post-natal vasculogenesis and to repair of damaged endothelium by incorporation into the vessel wall, secretion of paracrine hormones and stimulation of angiogenesis. Since the first description of the putative EPCs in 1997, and the role of these cells in neovascularisation of mouse and rabbit ischaemic limbs was originally described, there has been an explosion of research into the role of EPCs in human cardiovascular disease. There is now a large body of direct and indirect evidence to support an important role for EPCs in cardiovascular disease processes. This book chapter explores the following: 1. Correlation between EPCs and other cardiovascular risk markers 2. EPCs in patients with established cardiovascular disease 3. Reversible defects in EPC number and function in patients with an increased cardiovascular risk 4. Statins and EPC biology 5. The effect on EPCs of other interventions known to reduce cardiovascular risk - EPCs and treatment of diabetes, hypertension, subclinical hypothyroidism 6. Beneficial effects of EPC-based therapies animal models of ischaemia 7. Human Studies of EPC-based therapies A lower level of circulating EPCs and reduced EPC function in vitro are associated with an increased cardiovascular risk. The accumulated evidence suggests that a balance between the damaging effects of conventional cardiovascular risk factors and the ability of circulating EPCs to affect endothelial repair determines this cardiovascular risk.

The objective of this study was to evaluate the potential of bovine IVF blastocysts at different stages of embryonic development in establishing ESC-like. Furthermore, blastocysts cultured in medium containing (10%) and (2.5%) fetal calf serum (FCS) were compared to determine if the serum concentration during in vitro culture alters the blastocyst's potential to establish ESC-like culture. It was observed that only ICM's from expanded blastocysts adhered to the monolayer (n=160) independent of the concentration of serum used during IVF culture. There were no observable differences in potential to establish ESC-like in embryos cultured with 2,5% or 10% FCS . The bFGF didn´t seems to be required for maintenance of bovine ESC-like regardless of culture conditions. Blastocysts and colonies in primary culture and after the first passage were positive for Oct4, Nanog, SSEA-3 and TRA-1-81. Expanded blastocysts gave rise to ESC-like colonies, and the addition of LIF was sufficient to maintain cells undifferentiated in culture.

Objective: To evaluate the therapeutic and safety efficacy of a naturally occurring mineral supplementation in the treatment of symptomatic knee osteoarthritis (OA).

Patients and methods: A prospective, single centre, study of 50 patients aged 50 years and above with painful and radiological Osteoarthritis of knees was carried out for one year. Patients received 40 drops of naturally occurring commercially available mineral supplement concentrate mineral drops purportedly derived from the Great Salt Lake in Utah. Efficacy was objectively confirmed by evaluating changes in the thickness of articular cartilage, joint space width, synovial fluid analysis and subjectively by changes in WOMAC scores and 6 Minute pain-free Walking Distance.

Results: The composite WOMAC scores were significantly improved by 17.2 points from a mean of 52 at baseline by year end. 18 (41%) patients showed improvement of more than 100 feet for the pain free distance covered during a 6 minute walk at one year follow-up. Ultrasonologicaly, at one year cartilage thickness improved by at least 0.01 mm in 9 (21%) patients. Though radiologicallynone of patient showed increase in joint space it was noticed that only 2(4.6%) patients had decline of joint space width of more than 0.5 mm. Average cell count reduced to 205/microlitre from a value of 520/microlitre at the start of study suggesting that the mineral supplement used had structural efficacy.

Conclusion: Clinically relevant, statistically significant symptomatic and statistically insignificant structural improvement occurred over 1 year period in patients receiving the naturally occurring mineral supplement. The protection of the joint cartilages from progressive degeneration during osteoarthritis by these supplements indicates towards a chondrocyte regenerative potential of this supplement. Such regeneration may occur through activation of tissue specific adult chondrocyte precursors or stem cells.

Senescence of cells is associated with shortened or damaged telomeres and is characterized by permanent exit from the cell cycle and altered function. Cellular senescence is caused by repeated cell division, and also conditions of stress including inflammation and reactive oxygen species can lead to the development of premature senescence. At the cellular level, proliferative and oxidative-stress induced cell senescence related to a pro-inflammatory state might strongly contribute to age-associated impaired tissue and organ functions. Vascular cells (endothelial cells, vascular smooth muscle cells) and bone marrow-derived endothelial progenitor cells have been repeatedly shown to have pivotal role in the maintenance and regeneration of cardiovascular tissue. Therefore, the molecular mechanisms of vascular cell senescence have been extensively studied. However, therapeutic approaches to prevent cellular senescence in cardiovascular disease (CVD) are still limited. Hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and fibroblast growth factor (FGF) are all potent angiogenic growth factors in animal models of ischemia, but their therapeutic effects are not the same in animal experiments and clinical trials. A multicenter, double-blind, placebo-controlled phase III clinical trial in Japan and a US phase II clinical trial of HGF gene therapy for critical limb ischemia (CLI) demonstrated a significant improvement in primary end points and an increase in transcutaneous partial pressure of oxygen even after one year compared with placebo, whereas effectiveness of VEGF and FGF treatment for CLI has not yet been shown. Moreover, our recent publication and another researcher demonstrated that HGF acts as an anti-inflammatory cytokine, while VEGF and FGF act as pro-inflammatory cytokine. This review overviews the outcomes of clinical trials using angiogenic growth factors, which have shown a dramatic effect in several animal studies. Additionally, interventions with HGF aimed at improving the regenerative capacity of stem/progenitor cells and vascular cells by preventing cellular senescence are discussed.