scholarly journals Modulation of osteoblast behaviour by tenascin

1996 ◽  
Vol 109 (6) ◽  
pp. 1597-1604 ◽  
Author(s):  
E.J. Mackie ◽  
S. Ramsey
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Cell Lines ◽  
Alkaline Phosphatase Activity ◽  
Matrix Protein ◽  
Bone Matrix ◽  
Cytochalasin D ◽  
Extracellular Matrix Protein ◽  
Cell Rounding ◽  
Umr 106

The extracellular matrix protein tenascin is secreted by osteoblasts but absent from mineralized bone matrix. The current study was undertaken to test the hypothesis that tenascin regulates osteoblast behaviour. Three osteoblast-like cell lines UMR-106, ROS-17/2.8 (rat) and SAOS-2 (human) were used to investigate the role of tenascin in osteoblast morphology, differentiation and proliferation. Two of three cell lines adhered specifically to tenascin, remaining round and failing to spread. Tenascin as a substratum stimulated alkaline phosphatase activity (a marker of osteoblast differentiation) in two of three cell lines. Moreover, anti-tenascin in the medium caused a reduction in alkaline phosphatase levels in all three cell lines. Anti-tenascin also inhibited collagen synthesis, an important osteoblast function. Since it seemed possible that tenascin may exert its effects on cell function through its ability to cause cell rounding, the ability of cell shape change alone to influence alkaline phosphatase levels was investigated. Cells were incubated in the presence of cytochalasin D and alkaline phosphatase levels assayed. Alkaline phosphatase activity was not elevated by cytochalasin D treatment, indicating that cell rounding alone is insufficient to mimic the effect of tenascin. Anti-tenascin caused a slight increase in proliferation of SAOS-2 cells, indicating that tenascin is itself inhibitory. In ROS 17/2.8 and UMR-106 cells, in contrast, proliferation was inhibited by anti-tenascin. The results presented here indicate that tenascin is able to stimulate osteoblastic differentiation and that endogenous tenascin helps to maintain the functional state of cultured osteoblast-like cells.

Alkaline phosphatase activity from human osteosarcoma cell line SaOS-2: an isoenzyme standard for quantifying skeletal alkaline phosphatase activity in serum.

1989 ◽  
Vol 35 (2) ◽  
pp. 223-229 ◽  
Author(s):  
J R Farley ◽  
E Kyeyune-Nyombi ◽  
N M Tarbaux ◽  
S L Hall ◽  
D D Strong
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Cell Lines ◽  
Alkaline Phosphatase Activity ◽  
Osteosarcoma Cell ◽  
Kinetic Assay ◽  
Human Osteosarcoma ◽  
Alp Activity ◽  
Human Osteosarcoma Cell ◽  
Skeletal Alkaline Phosphatase

Abstract Earlier we described a kinetic assay for quantifying skeletal alkaline phosphatase (ALP) isoenzyme activity in serum. The precision of the assay depends on including ALP standards for the skeletal, hepatic, intestinal, and placental isoenzymes. We wondered whether human osteosarcoma cells could provide an efficient alternative to human bone or Pagetic serum as a source of the skeletal ALP standard. ALP activities prepared from five human osteosarcoma cell lines were compared with a bone-derived ALP standard with respect to heat stability and sensitivity to chemical effectors. Two of the cell lines (SaOS-2 and TE-85) contained ALP activities that resembled the bone-derived standard. We selected SaOS-2 cells for additional evaluation (as a potential source of isoenzyme standard), because they contained 40-50 times more ALP activity than did the TE-85 cells. To include the SaOS-2 cell-derived ALP activity in the quantitative isoenzyme assay, we diluted the enzyme in a solution containing heat-inactivated (i.e., ALP-negative) human serum. Surprisingly, this dilution caused a 60-125% increase in maximum enzyme activity. In the quantitative assay of ALP isoenzyme in serum, the SaOS-2 derived ALP was indistinguishable from the serum skeletal ALP standard, with respect to the above criteria and assay variations. Evidently ALP from SaOS-2 cells is suited as a standard for measuring skeletal ALP activity in this assay.

An activity-based fluorescent probe and its application for differentiating alkaline phosphatase activity in different cell lines

2020 ◽  
Vol 56 (87) ◽  
pp. 13323-13326
Author(s):  
Yong He ◽  
Junli Yu ◽  
Xiangzi Hu ◽  
Shumei Huang ◽  
Lili Cai ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Fluorescent Probe ◽  
Cell Lines ◽  
Alkaline Phosphatase Activity

An activity-based fluorescent probe with the characteristics of AIE + ESIPT has been reported for differentiating the alkaline phosphatase activity in different cell lines.

299 A FEATURE OF SELF-RENEWAL PORCINE EMBRYONIC STEM CELL-LIKE CELL LINES ESTABLISHED BY INHIBITORS

2013 ◽  
Vol 25 (1) ◽  
pp. 297
Author(s):  
S. Haraguchi ◽  
T. Tokunaga ◽  
T. Furusawa ◽  
K. Ohkoshi ◽  
M. Nakai ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Stem Cell ◽  
Embryonic Stem Cell ◽  
Phosphatase Activity ◽  
Cell Lines ◽  
Alkaline Phosphatase Activity ◽  
Embryonic Stem ◽  
Self Renewal ◽  
Established Cell Lines ◽  
Established Cell

Despite meticulous attempts for more than two decades, establishment of authentic porcine embryonic stem cell (ESC) from pig has never been successful. Although putative porcine ESC-like cells have been reported, such cell lines easily lose the ability of self-renewal, becoming extinct or differentiating after only a limited number of passages in culture. Porcine ESC-like cells exhibiting the property of self-renewal rather than pluripotency are considered a valuable resource in applications such as drug screening and toxicology testing in humans and livestock, and in veterinary medicine. In the present study, we evaluated the effect of glycogen synthase kinase 3β (GSK3β) inhibitor CHIR99021 and Erk signalling inhibitor PD184352 for use in establishing ESC-like cell lines derived from the inner cell mass (ICM) of porcine blastocysts produced in vitro. These ICM-derived cell lines were initially cultured and passaged in conventional human ES medium. They displayed so-called ESC-like morphology; for example, the isolated colonies began to grow as a monolayer with coarse cell–cell boundaries, in which the cells exhibited polygonal boundaries, high nuclear/cytoplasmic ratios, abundant lipid-like inclusions, alkaline phosphatase activity, and expression of markers of undifferentiated cells such as OCT4 and NANOG. After transfer to culture in ES medium containing the inhibitors, the morphology of the colony was dramatically changed, displaying a closely packed and smooth-edged colony with tight cell–cell boundaries. Remarkably, growth of the established cell lines is leukemia inhibitory factor (LIF)-dependent. The inclusion of inhibitors supports self-renewal, thus enabling continuous culture for over 100 passages while maintaining an undifferentiated state. High-passage-number cells continued to express undifferentiated marker genes and showed alkaline phosphatase activity and telomerase activity with an X chromosome status of XaXi. We further investigated the potential for differentiation of the established cell lines. The cells could easily form embryoid body-like spheres in suspension culture. When either the spheres or ESC-like cells were inoculated under the kidney or testis capsules of nude mice, classical teratoma formation was not observed after 2 to 3 months. However, histological analyses revealed apparent invasive proliferation derived from porcine cells. Although further analyses are required to characterise the property of the porcine ESC-like cells, we have recently succeeded in establishment of green fluorescent protein (GFP)-expressing stable cells lines, which will be useful for further investigation.

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