Purification of alkaline phosphatase from extracellular vesicles of fracture callus cartilage

Correlative morphometric and biochemical analysis of purified extracellular matrix vesicles from rat alveolar bone

“…The present results, when studied in view of the similarity found in the vesicular fractional area of the three purified preparations and the higher protein content of the "'heavy" fraction, suggest that the latter prepara- tion contains a relatively high amount of electronlucent vesicles and contaminating protein. The resolution of the sucrose gradient into two vesicular fractions is in agreement with previous studies on vesicles isolated from cartilage [19]. However, Hubbard et al [5] found that the highest calcium and phosphate loading activity occured in the "heavy" fraction of cartilage matrix vesicles.…”

Scanning Electron Microscopy of Cartilage

“…In these calcifying tissues matrix vesicles pre cede mineral deposition and are thought to initiate the process. It is possible to isolate the vesicles from cartilage for biochemical analysis and TEM (Ali, 1979;Kahn et al, 1978;Anderson, 1976), but the isolates have not been studied with SEM, perhaps because it would not appear to be useful.…”

Biological Calcification

“…One of the most distinctive properties of matrix vesicles is that they show alkaline phosphatase activity (Ali et al 1970(Ali et al , 1971Matsuzawa and Anderson 1971;Larsson 1973;Salomon 1974;Majeska and Wuthier 1975;Bernard 1978;Fortuna et al 1978Fortuna et al , 1980Kahn et al 1978;Takagi and Toda 1979;Väänänen and Korhonen 1980;Watkins et al 1980;Morris et al 1986Morris et al , 1992ade Bernard et al 1986;Miller and DeMarzo 1988;Henson et al 1995;Herbert et al 1997;Kirsch and Claassen 2000;Hoshi et al 2001). Light microscope studies on epiphyseal cartilage, as well as on bone and other calcifying tissues ( Fig.…”

“…9.5), have shown that enzyme activity first appears on the membrane of osteoblasts and chondrocytes and, as globule-like precipitates, around and outside the cell membrane of lower maturing chondrocytes and hypertrophic chondrocytes (Morris et al 1986;Akisaka and Gay 1985b;Bianco 1990). 9.5, inset) (de Bernard et al 1986;Morris et al 1986Morris et al , 1992aBianco 1990;Masuhara et al 1992) and by the presence of alkaline phosphatase activity in isolated matrix vesicles (Ali et al 1970(Ali et al , 1971Majeska and Wuthier 1975;Fortuna et al 1978;Kahn et al 1978;Väänänen and Korhonen 1980;Watkins et al 1980). These results were confirmed by alkaline phosphatase immunohistochemistry ( Fig.…”