Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.3.1 (alkaline phosphatase)
47,916 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human recombinant bone morphogenetic protein-2 (rhBMP-2) immobilized on the surface of metal implants can facilitate osseointegration. Here, we describe a cell reporter assay useful for quantifying small amounts of immobilized rhBMP-2 on various materials. The peptide was dotted and heat-fixed on titanium, 316L stainless steel, nitrocellulose, or glass, and its distribution was monitored by in situ biotinylation followed by detection with the avidin-biotin method. Bioactivity of rhBMP-2 was demonstrated by means of a confluent layer of osteoblastic MC3T3-E1 cells that evenly covered rhBMP-2-free and rhBMP-2-loaded surface areas, as shown with epifluorescence microscopy of calcein acetoxymethyl (AM)-loaded cells. Expression of osteocalcin, fibronectin, actin, and vimentin increased where cells were located on rhBMP-2 dotted areas, but the signal:noise ratio was too low to bioassay the peptide. However, local pronounced expression of alkaline phosphatase was used to quantify BMP-2 in the range of 5-80 ng/dot by means of a cytochemical color reaction for alkaline phosphatase and image analysis of resulting dots. The lower detection limit was in the order nitrocellulose > glass > titanium > 316L steel. We conclude that the cell reporter assay is useful to assess biological activity of rhBMP-2 even after immobilization on three-dimensional implant materials.
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PMID:A reporter-cell assay for the detection of BMP-2 immobilized on porous and nonporous materials. 1212 93

The availability of cell lines that retain their differentiation programs is important for the study of differentiated cell types and the development of cell therapies. DNA tumor virus genes are often used to establish cell lines from primary culture for the analysis of cell-specific functions. To ascertain whether viral immortalizing or transforming genes differed in their effects on cellular differentiation programs, the E1A 12S (WT12S) gene of adenovirus and the large T antigen (LT) gene of SV40 were used to derive stable cell lines from primary kidney. The resultant cell types exhibited very different morphologies, growth and behavior patterns, differentiation states, and plasticities. Renal cells immortalized by LT exhibited branching tubulogenesis in response to Matrigel. This was in contrast to their behavior under normal culture conditions, wherein they were less differentiated, very nonadhesive, very rapidly growing, and transformed. These cells coexpressed adult epithelial (keratin) and embryonic mesenchymal (vimentin, osteopontin, FSP1, PAX-2, and WT1) genes. WT12S-immortalized cells grown on or in Matrigel formed cysts or tubules, consistent with their expression profiles, which consisted of both epithelial and adult kidney markers (E-cadherin, alpha-catenin, circumferential actin filaments (CAF), alkaline phosphatase, aminopeptidase M, BMP7, or podocalyxin), but not embryonic/mesenchymal markers (PAX-2 or WT1). The WT12S-expressing cells were well differentiated, adhesive, slow growing, and nontransformed. Thus, cells expressing WT12S maintained their original differentiation status and were less sensitive to reprogramming, while cells expressing LT were dedifferentiated, but had the potential for reprogramming by exogenous factors.
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PMID:Differential effects of DNA tumor virus genes on the expression profiles, differentiation, and morphogenetic reprogramming potential of epithelial cells. 1220 1

The presence of non-hematopoietic stem cells in the human umbilical cord blood (hUCB) is debated. In this study, we report the isolation of a population of fibroblast-like cells with osteogenic and adipogenic potential that resembles the stromal stem cells found in the bone marrow. Low-density mononuclear cells isolated from hUCB formed few adherent colonies with fibroblast-like morphology after a few days in culture. At confluence, the polyclonal cell populations were characterized. Using FACS analysis and immunocytochemistry, the cells were found to express HLA-ABC, CD9, vimentin, the b subunit of prolyl-4-hydroxylase, integrins a1(CD49a), integrin a3 (CD49c), integrin a5(CD49e), and cytokeratin 18. Furthermore, the cells expressed constitutively transcripts of osteoblast-specific markers: Cbfa1/Runx2, alkaline phosphatase (AP), and collagen type I, and formed a mineralized matrix in vitro visualized by Alizarin red staining. In the presence of normal horse serum and dexamethasone (10(-7) M), the cells formed foci of adipocytes. When the cells were implanted mixed with hydroxyapatite/tricalcium phosphate powder in the subcutis of immunocompromised mice for 8 weeks, they formed osteogenic tissue and a myelosupportive microenviroment that enclosed hematopoietic cells and adipocytes. Our results demonstrate the presence of circulating stem cells with osteogenic and adipogenic differentiation potential in hUCB and may encourage the use of hUCB as a potential source for stem cells to be utilized in cell therapy protocols for various diseases.
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PMID:The human umbilical cord blood: a potential source for osteoblast progenitor cells. 1245 62

There has been considerable variability in the reported results of immunohistochemical staining for some diagnostically relevant antigens. Our objectives in this study were to (1) use a multitumor tissue microarray with tissue from 351 cases received in our department, representing 16 normal tissues and 47 different tumor types, to compare immunohistochemical staining results in our laboratory with published data, using a panel of 22 antibodies; (2) assess interlaboratory variability of immunohistochemical staining for S-100 using this microarray; and (3) test the ability of hierarchical clustering analysis to group tumors by primary site, based on their immunostaining profile. Tissue microarrays consisting of duplicate 0.6-mm cores from blocks identified in the hospital archives were constructed and stained according to our usual protocols. Antibodies directed against the following antigens were used: B72.3, bcl-2, carcinoembryonic antigen, c-kit, pankeratin, CD 68, CD 99, CK 5/6, CK 7, CK 8/18, CK19, CK 20, CK 22, epithelial membrane antigen, estrogen receptor, melan-A, p53, placental alkaline phosphatase, S-100, synaptophysin, thyroid transcription factor-1, and vimentin. Staining results on the array cases were compared with published results, and hierarchical clustering analysis was performed based on the immunohistochemical staining results. Unstained slides of the multitumor tissue microarray were sent to five other diagnostic immunohistochemistry laboratories and stained for S-100 protein. The staining results from the different laboratories were compared. Staining results using our current methods and samples from our laboratory were compatible with those described in the literature for most antigens. Placental alkaline phosphatase staining was not specific with our protocol, showing staining of a broad spectrum of different tumors; this finding initiated a review of our recent requests for placental alkaline phosphatase immunostaining and revealed two instances in which placental alkaline phosphatase positivity was incorrectly interpreted as evidence of a germ cell tumor. S-100 staining was less sensitive but more specific for the diagnosis of melanoma or neural tumor in our laboratory, compared to some published reports. Assessment of interlaboratory variability of S-100 immunostaining showed that there was more frequent staining of carcinomas in some laboratories, resulting in decreased specificity of S-100 staining in distinguishing melanoma from carcinoma. Hierarchical clustering analysis showed a strong trend for tumors to cluster by tissue of origin, but there were significant exceptions. We conclude that multiple-tumor microarrays are an efficient method for assessing the sensitivity and specificity of staining with any antibody used diagnostically. As a tool for quality assurance, they offer the advantage of taking into account local differences in tissue fixation, processing, and staining. They also allow cost-effective assessment of interlaboratory variability in immunohistochemical staining. Results of hierarchical clustering analysis show the potential for panels of immunohistochemical stains to identify the primary site of metastatic carcinomas but also confirm the limitations of currently available antibodies in giving unequivocal tissue-specific staining patterns.
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PMID:Tissue microarrays are an effective quality assurance tool for diagnostic immunohistochemistry. 1248 Oct 20

In vitro treatment with a pharmacological dose of simvastatin, a potent pro-drug of a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor, stimulates bone formation. In our study, simvastatin stimulated differentiation of osteoblasts remarkably in a dose-dependent manner, with minimal effect on proliferation. To identify the mediators of the anabolic effects of simvastatin on osteoblasts, we tried to identify and characterize simvastatin-induced proteins by using proteomic analysis. Calcyclin was significantly up-regulated by more than 10 times, and annexin I was also up-regulated by simvastatin. However, annexin III, vimentin, and tropomyosin were down-regulated. Up-regulated calcyclin mRNA by simvastatin was validated by reverse transcription in mouse calvarial cells. In confocal microscope analysis, green fluorescence protein-calcyclin fusion protein was ubiquitously observed in the of MC3T3-E1 cells transfected with green fluorescence protein-calcyclin cDNA containing plasmid and was quickly concentrated in the nucleus 20 min after simvastatin treatment. Overexpression of calcyclin cDNA stimulated both the proliferation and expression of alkaline phosphatase mRNA significantly, without exposure to simvastatin in MC3T3-E1 cells. However, both the rate of proliferation of the osteoblasts and the expression of alkaline phosphatase mRNA were suppressed significantly 1 day after treatment with the calcyclin-specific small interference RNA, and furthermore, simvastatin did not overcome this suppression in the small interference RNA-pretreated MC3T3-E1 cells. In conclusion, calcyclin is one of the candidate proteins that plays a role in osteoblastogenesis in response to simvastatin, although the precise functions of calcyclin in osteoblast remain to be verified.
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PMID:Calcyclin, a Ca2+ ion-binding protein, contributes to the anabolic effects of simvastatin on bone. 1497 29

Salter's type III and type IV growth plate injuries often induce bone bridge formation at the injury site. To understand the cellular mechanisms, this study characterized proximal tibial transphyseal injury in rats. Histologically, bony bridge trabeculae appeared on day 7, increased on day 10, and became well-constructed on day 14 with marrow. Prior to and during bone bridging, there was no cartilage proteoglycan metachromatic staining and no collagen-X immunostaining at the injury site, nor was there any up-regulation of BrdU-labelled chondrocyte proliferation at the adjacent physeal cartilage, suggesting no new cartilage formation at the injury site. However, infiltration of vimentin-immunopositive mesenchymal cells from metaphysis and epiphysis was apparent on day 3, with the mesenchymal population being prominent on days 7 and 10 and subsided on day 14. Among these infiltrates were osteoprogenitor precursors expressing osteoblast differentiation factor (cbf-alpha1) on day 3, along with some cbf-alpha1+ osteoblast-like cells lining bone trabeculae on days 7 and 10. Some mesenchymal cells and trabecula-lining cells were also alkaline phosphatase-immunopositive, further suggesting their osteoblast differentiation. From day 7 onwards, some trabecula-lining cells became osteocalcin-producing mature osteoblasts. These results suggest that bone bridge formation after growth plate injury occurs directly via intramembranous ossification through recruitment of marrow-derived osteoprogenitor cells.
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PMID:Intramembranous ossification mechanism for bone bridge formation at the growth plate cartilage injury site. 1501 5

A 72-year-old woman with von Recklinghausen's disease was referred to our hospital because of pain and muscle weakness in her thighs. She had elevated serum values of creatine kinase, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, and aldolase. Based on these results, a diagnosis of polymyositis was made. Treatment with prednisolone improved muscle strength, and laboratory values returned to normal. Computed tomography, magnetic resonance imaging of the abdomen, and 131I-metaiodobenzyl guanidine MIBG scintigraphy demonstrated a tumor 3 cm in diameter in the region of the left adrenal gland. Endocrinologic investigation disclosed elevation of serum and urine catecholamines. Since the blood pressure was normal, nonfunctioning pheochromocytoma was diagnosed clinically. The nonhypertensive course was attributed to reduced vascular response to noradrenaline. Serum lactate dehydrogenase. alkaline phosphatase. and asparate aminotransferase became elevated, and abdominal computed tomography showed a well-defined mass measuring 13 x 12 x 10 cm in the right lobe of the liver. The patient underwent right trisegmentectomy and left adrenalectomy. Histologically the adrenal tumor was a typical pheochromocytoma. The hepatic tumor was a leiomyosarcoma consisting of elongated spindle-shaped atypical cells arranged in intersecting bundles. Immunohistochemically, the cells of this tumor were reactive for alpha-smooth muscle actin and vimentin. The leiomyosarcoma recurred and metastasized to the liver. Eight months after onset of symptom, the patient developed hepatic coma and died. The mean age at presentation with pheochromocytoma in von Recklinghausen's disease patients age is 42 years. Our patient was considerably older. To the best of our knowledge this is the first report of a patient with von Recklinghausen's disease developing polymyositis. asymptomatic pheochromocytoma, and primary hepatic leiomyosarcoma and illustrates the need to remain aware of the possibility of cancer in von Recklinghausen's disease.
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PMID:[A patient with von Recklinghausen's disease associated with polymyositis, asymptomatic pheochromocytoma, and primary hepatic leiomyosarcoma]. 1523 55

Highly purified primitive hemopoietic stem cells express BMP receptors but do not synthesize bone morphogenetic proteins (BMPs). However, exogenously added BMPs regulate their proliferation, differentiation, and survival. To further explore the mechanism by which BMPs might be involved in hemopoietic differentiation, we tested whether stromal cells from long-term culture (LTC) of normal human bone marrow produce BMPs, BMP receptors, and SMAD signaling molecules. Stromal cells were immunohistochemically characterized by the presence of lyzozyme, CD 31, factor VIII, CD 68, S100, alkaline phosphatase, and vimentin. Gene expression was analyzed by RT-PCR and the presence of BMP protein was confirmed by immunohistochemistry (IHC). The supportive role of the stromal cell layer in hemopoiesis in vitro was confirmed by a colony assay of clonogenic progenitors. Bone marrow stromal cells express mRNA and protein for BMP-3, -4, and -7 but not for BMP-2, -5, and -6 from the first to the eighth week of culture. Furthermore, stromal cells express the BMP type I receptors, activin-like kinase-3 (ALK-3), ALK-6, and the downstream transducers SMAD-1, -4, and -5. Thus, human bone marrow stromal cells synthesize BMPs, which might exert their effects on hemopoietic stem cells in a paracrine manner through specific BMP receptors.
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PMID:Expression of bone morphogenetic proteins in stromal cells from human bone marrow long-term culture. 1531 83

The epiblast represents the final embryonic founder cell population with the potential for giving rise to all cell types of the adult body. The pluripotency of the epiblast is lost during the process of gastrulation. Large animal species have a lack of specific markers for pluripotency. The aim of the present study was to characterize the bovine epiblast cell population and to provide such markers. Bovine Day 12 and Day 14 embryos were processed for transmission-electron microscopy or immunohistochemistry. In Day 12 embryos, two cell populations of the epiblast were identified: one constituting a distinctive basal layer apposing the hypoblast, and one arranged inside or above the former layer, including cells apposing the Rauber layer. Immunohistochemically, staining for the octamer-binding transcription factor 4 (OCT4, also known as POU5F1), revealed a specific and exclusive staining of nuclei of the complete epiblast. Colocalization of vimentin and OCT4 was demonstrated. Only trophectodermal cells stained for alkaline phosphatase. Staining for the proliferation marker Ki-67 was localized to most nuclei throughout the epiblast. A continuous staining for zonula occludens-1 protein was found between cells of the trophectoderm and hypoblast but was not evident in the epiblast. A basement membrane, detected by staining for laminin, formed a "cup-like" structure in which the epiblast was located. The ventrolateral sides of the cup appeared to be incomplete. In conclusion, the bovine epiblast includes at least two cell subpopulations, and OCT4 was shown, to our knowledge for the first time, to be localized exclusively to epiblast cells in this species.
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PMID:Ultrastructural and immunohistochemical characterization of the bovine epiblast. 1553 64

In adult individuals when most tissues have progressively lost the ability to regenerate, bone maintains the potential for a continuous self remodeling. The bone marrow has been so far the main recognized source of osteoprogenitor cells that contribute to the turnover of the skeletal scaffold. The possibility though exists that a pool of osteoprogenitor cells resides within other adult tissues and in particular, as reported previously, in other connective tissues such as fat and skeletal muscle. In an attempt to identify an alternative source of osteoprogenitor cells other than bone marrow we looked into the skeletal muscle. A plastic adhering cell population, from now on referred to as skeletal muscle derived cells (SMDCs), was obtained from biopsies of human skeletal muscle. SMDCs were clonogenic and displayed a fibroblast-like morphology. The isolated cell population had a mesenchymal origin as indicated by abundant expression of type I collagen, fibronectin, and vimentin and appeared heterogeneous. SMDCs were positive for alpha smooth actin, and to a lesser extent for desmin and alpha sarcomeric myosin, two specific markers of the myogenic phenotype. Surprisingly though SMDCs expressed early markers of an osteogenic commitment as indicated by positive staining for alkaline phosphatase, osteopontin, and osteonectin. Under the appropriate stimuli, these cells deposited in vitro a mineralized bone matrix and a proteoglycan rich matrix. In addition, SMDCs cultured in the presence of low serum and insulin differentiated towards adipocytes developing abundant lipid droplets in the cytoplasm. Furthermore SMDCs formed three-dimensional bone tissue in vivo when implanted in an immunodeficient mouse, and a mature cartilage rudiment when maintained as a pellet culture. In summary, we report the isolation and characterization of a cell population from the human skeletal muscle not only able to express in vitro specific markers of distinct mesenchymal lineages (adipogenic, chondrogenic, and osteogenic), but most importantly, able to complete the differentiation pathway leading to the formation of bone and cartilage. In this respect SMDCs resemble bone marrow stromal cells (BMSCs).
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PMID:Bone and cartilage formation by skeletal muscle derived cells. 1574 52


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