As pioneer of tumor stem cell research, leukemia stem cell research has not only important theoretical significance, but also clinical application potential. The survival and development of stem cells are directly impacted by their microenvironment. The research on leukemia stem cells and their microenvironment are now becoming a hot topic. The author presumes that stem cells are a population with heterogenecity and hierarchy; any single cell from the population is difficult to form a clone; the interaction between the leukemia stem cell and its microenvironment can be described by the concept of leukemia stem cell niche. In this article, the leukemia cell population with heterogenecity and hierarchy as well as leukemia stem cell niche were summarized and discussed.
Cell Line, Tumor ; Humans ; Leukemia ; genetics ; pathology ; Neoplastic Stem Cells ; metabolism ; pathology ; Stem Cell Niche ; cytology ; Stromal Cells ; cytology ; immunology

Actins ; metabolism ; Breast ; cytology ; metabolism ; Breast Neoplasms ; metabolism ; pathology ; Cell Differentiation ; Female ; Humans ; Keratins ; metabolism ; Neoplastic Stem Cells ; metabolism ; pathology ; Signal Transduction ; Stem Cells ; cytology ; metabolism

In the adult brain, neural stem cells have been found in two major niches: the dentate gyrus and the subventricular zone [corrected]. Neurons derived from these stem cells contribute to learning, memory, and the autonomous repair of the brain under pathological conditions. Hence, the physiology of adult neural stem cells has become a significant component of research on synaptic plasticity and neuronal disorders. In addition, the recently developed induced pluripotent stem cell technique provides a powerful tool for researchers engaged in the pathological and pharmacological study of neuronal disorders. In this review, we briefly summarize the research progress in neural stem cells in the adult brain and in the neuropathological application of the induced pluripotent stem cell technique.
Hippocampus ; cytology ; metabolism ; Humans ; Induced Pluripotent Stem Cells ; cytology ; metabolism ; Models, Biological ; Neural Stem Cells ; cytology ; metabolism ; transplantation ; Neurodegenerative Diseases ; metabolism ; pathology ; prevention & control ; Neurogenesis ; Signal Transduction

Cell Proliferation ; Colony-Forming Units Assay ; Glioma ; pathology ; Hematopoietic Stem Cells ; pathology ; Humans ; Stem Cells ; cytology ; metabolism

OBJECTIVETo study the clinicopathologic features of combined hepatocellular-cholangiocarcinoma (cholangiolocellular type, CLC type) with stem cell features and its relationship to hepatic progenitor cells (HPCs).

METHODSClinical and histologic features of 26 cases of combined hepatocellular-cholangiocarcinoma (CLC type) were reviewed. Histochemistry was performed to confirm the type of mucin and immunohistochemical study was carried out for hepatocytic markers (Hep Par-1 and AFP) and biliary/HPCs markers (CK7, CK9, EMA, EpCAM, NCAM, CKIT).

RESULTSThe age of patients ranged from 51 to 82 years (mean 64 years). All 26 cases contained CLC and hepatocellular carcinoma components. CLC area was composed of mixtures of small monotonous glands with abundant fibrous stroma and lymphocytic infiltrate. Tumor cells were cuboidal, smaller in size than normal hepatocytes, with basophilic cytoplasm and round nuclei. All cases, especially at the tumor boundary, showed HCC-like trabecular areas characterized by mildly atypical tumor cells with abundant eosinophilic cytoplasm and little stroma. Out of 26 cases, 21 showed definite glandular formation with mucin production, representing intrahepatic cholangiocarcinoma areas. The three distinct areas showed transitional zones merging with each other. The surrounding liver tissue showed cirrhosis and chronic hepatitis with varying degrees of fibrosis and periportal ductular reaction. Immunohistochemistry showed that biliary/HPC markers (CK7, CK9, EMA, EpCAM, NCAM and CKIT) were strongly positive in CLC area in almost all cases, similar to the staining pattern of ductular reaction. In HCC-like areas, CK7 and CK19 were positive in all cases and the expression rates of EMA, EpCAM, NCAM, CKIT, AFP, Hep Par-1 were 80.8% (21/26), 88.5% (23/26), 84.6% (22/26), 88.5% (23/26), 46.2% (12/26) and 53.8% (14/26) respectively, similar to the staining pattern of intermediate hepatocytes. In ICC areas, CK7, CK9, EMA and EpCAM were positive in all cases without the expression of NCAM and CKIT.

CONCLUSIONThe clinicopathologic findings and immunohistochemical results in this study highly suggest a hepatic progenitor cell origin of combined hepatocellular-cholangiocarcinoma (CLC type).

Bile Duct Neoplasms ; pathology ; Biomarkers ; metabolism ; Carcinoma, Hepatocellular ; pathology ; Cholangiocarcinoma ; pathology ; Hepatocytes ; cytology ; Humans ; Immunohistochemistry ; Liver Cirrhosis ; pathology ; Liver Neoplasms ; pathology ; Mucins ; metabolism ; Stem Cells ; cytology

The purpose of this study was to elucidate the origin and cellular composition of retrocorneal membranes (RCMs) associated with chemical burns using immunohistochemical staining for primitive cell markers. Six cases of RCMs were collected during penetrating keratoplasty. We examined RCMs with hematoxylin and eosin (H&E), periodic acid-Schiff (PAS) staining and immunohistochemical analysis using monoclonal antibodies against hematopoietic stem cells (CD34, CD133, c-kit), mesenchymal stem cells (beta-1-integrin, TGF-beta, vimentin, hSTRO-1), fibroblasts (FGF-beta, alpha-smooth muscle actin), and corneal endothelial cells (type IV collagen, CD133, VEGF, VEGFR1). Histologic analysis of RCMs revealed an organized assembly of spindle-shaped cells, pigment-laden cells, and thin collagenous matrix structures. RCMs were positive for markers of mesenchymal stem cells including beta-1-integrin, TGF-beta, vimentin, and hSTRO-1. Fibroblast markers were also positive, including FGF-beta and alpha-smooth muscle actin (SMA). In contrast, immunohistochemical staining was negative for hematopoietic stem cell markers including CD34, CD133 and c-kit as well as corneal endothelial cell markers such as type IV collagen, CD133 except VEGF and VEGFR1. Pigment-laden cells did not stain with any antibodies. The results of this study suggest that RCMs consist of a thin collagen matrix and fibroblast-like cells and may be a possible neogenetic structure produced from a lineage of bone marrow-derived mesenchymal stem cells.
Adult ; Aged ; Antigens, CD/metabolism ; Cornea/*cytology/pathology ; Cytokines/metabolism ; Endothelial Cells/cytology/metabolism ; Female ; Fibroblasts/cytology/metabolism ; Hematopoietic Stem Cells/cytology/metabolism ; Humans ; Immunohistochemistry ; Intercellular Signaling Peptides and Proteins/metabolism ; Male ; Mesenchymal Stromal Cells/cytology/metabolism ; Middle Aged ; Stem Cells/cytology/*metabolism

This study was aimed to investigate the biological characteristics of osteoblasts from patients with myelodysplastic syndrome (MDS) and their supportive capacity for hematopoiesis in vitro. A two-dimensional culture system was constructed by using osteoblasts derived from human marrow mesenchymal stem cells (MSC); MSCs were isolated from bone marrow of MDS patients and normal individuals and were cultured; the third passage of MSCs were induced into osteoblasts which were treated with mitomycin C and confluenced into a feeder layer. Ficolled bone marrow mononuclear cells were obtained from normal individuals and seeded into the two-dimensional culture system to culture in vitro without exogenous cytokines. By using colony-forming assay, the ability of the two-dimensional system to culture HPCs was observed. The cytokine expression of osteoblasts from MDS patient bone marrows in mRNA level was detected by RT-PCR and was compared with human osteoblast cell line hFOB1.19. The results showed that the osteoblasts from MDS patients could support short-term survival of GM-CFC in condition without exogenous cytokines, that is, osteoblasts played a crucial role in regulation of HPC growth. The results of RT-PCR clearly demonstrated that the osteoblast cell line hFOB1.19 expressed SCF, IL-6, SDF-1alpha, G-CSF and GM-CSF. The same expression patterns of above cytokines were also seen in osteoblasts derived from BM-MSCs of MDS patients and normal individuals, but these cells did not express GM-CSF. It is concluded that the biological characteristics of osteoblasts from bone marrow of MDS patients are generally not different from those of osteoblasts from normal bone marrow. Both of them can support GM -CFC to form colonies in vitro, it may be associated with expressing important related cytokines by osteoblasts.
Cytokines ; metabolism ; Granulocyte-Macrophage Colony-Stimulating Factor ; metabolism ; Granulocyte-Macrophage Progenitor Cells ; cytology ; Hematopoietic Stem Cells ; cytology ; Humans ; Interleukin-6 ; metabolism ; Myelodysplastic Syndromes ; metabolism ; pathology ; Osteoblasts ; metabolism ; physiology ; RNA, Messenger ; metabolism ; Stem Cell Factor ; metabolism

We hypothesized that the formation and differentialtion of osteoclasts are accelerated and the potential of bone resorption is increased in the hemiplegic bone marrow in the early stage of stroke. We randomly divided white female Sprague-Dawley (SD) rats (n = 30) into two groups, stroke (n = 15) and sham group (n = 15). On the 7th day after stroke, after cutting away the epiphyses of the femurs and tibias, diaphyseal channels were flushed using alpha-minimum essential medium (alpha-MEM) and bone marrow cells were collected. Bone marrow stem cells, which were extracted from the femur and tibia, were cultured on the 7th day after middle cerebral artery occlusion. We then estimated the ratio of non-adherent cells to total bone marrow cells that included osteoclast precursor cells. After culturing these cells separately, cells that tested positive on the tartrate resistant acid phosphatase (TRAP) were counted and bone resorption was evaluated by using the OAAS(TM) plate. In comparison to the control group, the stroke group showed a higher increase of non-adherent cells in the hemiplegic side bone marrow. In addition, after the primary culture, the stroke group showed an increased number of TRAP positive cells and a higher degree of bone resorption estimated by OAAS(TM) plate. As a result, osteoclastogenesis and osteoclast differentiation are accelerated and the potential of bone resorption is increased in the hemiplegic bone marrow and these changes are detected as early as within the first week after middle cerebral artery occlusion in SD rats.
Animals ; Bone Marrow Cells/cytology/drug effects ; Bone Resorption/*physiopathology ; Cell Differentiation ; Cell Separation ; Cells, Cultured ; Female ; Femur/cytology ; Osteoclasts/cytology ; Rats ; Rats, Sprague-Dawley ; Stem Cells/cytology/metabolism ; Stroke/*metabolism/pathology ; Tartrates/pharmacology ; Tibia/cytology

BACKGROUNDEndothelial dysfunction is thought to be critical events in the pathogenesis of Alzheimer's disease (AD). Endothelial progenitor cells (EPCs) have provided insight into maintaining and repairing endothelial function. To study the relation between EPCs and AD, we explored the number of circulating EPCs in patients with AD.

METHODSA total of 104 patients were recruited from both the outpatients and inpatients of the geriatric neurology department at General Hospital, Tianjin Medical University. Consecutive patients with newly diagnosed AD (n = 30), patients with vascular dementia (VaD, n = 34), and healthy elderly control subjects with normal cognition (n = 40) were enrolled after matching for age, gender, body mass index, medical history, current medication and Mini Mental State Examination. Middle cerebral artery flow velocity was examined with transcranial Doppler. Endothelial function was evaluated according to the level of EPCs, and peripheral blood EPCs was counted by flow cytometry.

RESULTSThere were no significant statistical differences of clinical data in AD, VaD and control groups (P > 0.05). The patients with AD showed decreased CD34-positive (CD34(+)) or CD133-positive (CD133(+)) levels compared to the control subjects, but there were no significant statistical differences in patients with AD. The patients with AD had significantly lower CD34(+)CD133(+) EPCs (CD34 and CD133 double positive endothelial progenitor cells) than the control subjects (P < 0.05). In the patients with AD, a lower CD34(+)CD133(+) EPCs count was independently associated with a lower Mini-Mental State Examination score (r = 0.514,P = 0.004). Patients with VaD also showed a significant decrease in CD34(+)CD133(+) EPCs levels, but this was not evidently associated with the Mini-Mental State Examination score. The changes of middle cerebral artery flow velocity were similar between AD and VaD. Middle cerebral artery flow velocity was decreased in the AD and VaD groups and significantly lower than the normal control group (P < 0.01). There was no significant difference of the blood flow velocity between the AD and VaD patients (P > 0.05).

CONCLUSIONSThe results provided evidence that patients with AD have reduced circulating EPCs. Endothelial function is impaired in patients with AD and vascular factors have a role in the pathogenesis of AD. CD34(+)CD133(+) EPCs may be a novel biomarker of AD dementia.

AC133 Antigen ; Aged ; Alzheimer Disease ; metabolism ; pathology ; Antigens, CD ; metabolism ; Antigens, CD34 ; metabolism ; Dementia, Vascular ; metabolism ; pathology ; Endothelial Cells ; cytology ; metabolism ; Female ; Glycoproteins ; metabolism ; Humans ; Male ; Peptides ; metabolism ; Stem Cells ; cytology ; metabolism

With their capability to undergo unlimited self-renewal and to differentiate into all cell types in the body, human embryonic stem cells (hESCs) hold great promise in human cell therapy. However, there are limited tools for easily identifying and isolating live hESC-derived cells. To track hESC-derived neural progenitor cells (NPCs), we applied homologous recombination to knock-in the mCherry gene into the Nestin locus of hESCs. This facilitated the genetic labeling of Nestin positive neural progenitor cells with mCherry. Our reporter system enables the visualization of neural induction from hESCs both in vitro (embryoid bodies) and in vivo (teratomas). This system also permits the identification of different neural subpopulations based on the intensity of our fluorescent reporter. In this context, a high level of mCherry expression showed enrichment for neural progenitors, while lower mCherry corresponded with more committed neural states. Combination of mCherry high expression with cell surface antigen staining enabled further enrichment of hESC-derived NPCs. These mCherry(+) NPCs could be expanded in culture and their differentiation resulted in a down-regulation of mCherry consistent with the loss of Nestin expression. Therefore, we have developed a fluorescent reporter system that can be used to trace neural differentiation events of hESCs.
Animals ; Cell Differentiation ; Cell Line ; Embryonic Stem Cells ; cytology ; metabolism ; transplantation ; Gene Knock-In Techniques ; Genes, Reporter ; Homologous Recombination ; Humans ; Luminescent Proteins ; genetics ; Mice ; Mice, SCID ; Nestin ; genetics ; Neural Stem Cells ; cytology ; metabolism ; Neurons ; cytology ; metabolism ; Teratoma ; pathology