Membranous particles in calcifying cartilage matrix.
01 May 1970-Annals of the New York Academy of Sciences (John Wiley & Sons, Ltd)-Vol. 32, Iss: 5, pp 619-630
About: This article is published in Annals of the New York Academy of Sciences.The article was published on 1970-05-01. It has received 73 citations till now.
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TL;DR: The matrix vesicles possess enzymes that can increase the local concentration of orthophosphate and thus could lead to the formation of hydroxyapatite, and may also provide a mechanism for ATP-dependent transport of calcium or phosphate into the lumen of the vesicle with resultant mineralization.
Abstract: Matrix vesicles, associated with initial calcification in cartilage, have been isolated from bovine fetal epiphyseal cartilage. Cartilage was digested with collagenase, then partitioned into seven fractions by differential centrifugation. The cellular fractions contained over 80% of the DNA in the digest. The extracellular fraction that contained matrix vesicles, in which apatite crystals were often seen on electron microscopy, also displayed the highest specific activity for alkaline phosphatase, pyrophosphatase, ATPase, and 5'-AMPase (EC 3.1.3.1., 3.6.1.1, 3.6.1.3, and 3.1.3.5, respectively). Most of the acid phosphatase (EC 3.1.3.2) activity, on the other hand, was found in the cellular fractions, indicating that matrix vesicles are quite distinct from lysosomes. This appears to be the first instance of isolation of membrane-bounded extracellular particles from any normal tissue. The matrix vesicles possess enzymes that can increase the local concentration of orthophosphate and thus could lead to the formation of hydroxyapatite. The membrane-bounded matrix vesicles may also provide a mechanism for ATP-dependent transport of calcium or phosphate into the lumen of the vesicles with resultant mineralization.
539 citations
TL;DR: Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties of the tooth and bone in addition to promoting more natural repair of surrounding tissues.
Abstract: Biomineralization is a dynamic, complex, lifelong process by which living organisms control precipitations of inorganic nanocrystals within organic matrices to form unique hybrid biological tissues, for example, enamel, dentin, cementum, and bone. Understanding the process of mineral deposition is important for the development of treatments for mineralization-related diseases and also for the innovation and development of scaffolds. This review provides a thorough overview of the up-to-date information on the theories describing the possible mechanisms and the factors implicated as agonists and antagonists of mineralization. Then, the role of calcium and phosphate ions in the maintenance of teeth and bone health is described. Throughout the life, teeth and bone are at risk of demineralization, with particular emphasis on teeth, due to their anatomical arrangement and location. Teeth are exposed to food, drink, and the microbiota of the mouth; therefore, they have developed a high resistance to localized demineralization that is unmatched by bone. The mechanisms by which demineralization-remineralization process occurs in both teeth and bone and the new therapies/technologies that reverse demineralization or boost remineralization are also scrupulously discussed. Technologies discussed include composites with nano- and micron-sized inorganic minerals that can mimic mechanical properties of the tooth and bone in addition to promoting more natural repair of surrounding tissues. Turning these new technologies to products and practices would improve health care worldwide.
408 citations
Cites background from "Membranous particles in calcifying ..."
...Pioneering studies have suggested the role of mitochondria in taking in large amounts of Ca and PO 4 ions, accumulating them, and delivering calcium phosphate in membrane bound vesicles to the extracellular spaces of mineralizing cartilage and bone.(35,48,49) Matrix vesicles are extracellular, membrane-invested vesicles 50–200 nm in diameter and are formed by polarized budding from the surface membrane of chondrocytes, osteoblasts, and odontoblasts....
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TL;DR: The determination of calcium mass‐fraction in one microarea of a vesicle within a section of rabbit epiphyseal plate cartilage is presented in detail in order to display all steps of the processing of the data.
Abstract: SUMMARY
The quantitative X-ray microanalysis of ultrathin biological sections is exemplified by a recent study of the distribution of calcium in mineralizing cartilage and bone. The determination of calcium mass-fraction in one microarea of a vesicle within a section of rabbit epiphyseal plate cartilage is presented in detail in order to display all steps of the processing of the data. Mass fractions are obtained from an equation which is approximate but which is adequately accurate for most cases of interest, specifically for ultrathin biological sections where the analysed area consists predominantly of organic matrix. We shall examine the physical assumptions behind the computation, and the extent to which these assumptions have been verified in the analytical microscope.
The purpose of this paper is to describe in detail the scheme of data collection and processing, which has now been in use for some years in the Cavendish Laboratory, for the measurement of local elemental mass fractions in thin biological specimens in instruments like the EMMA. After an outline of the physical theory we shall describe the handling of the data by means of working through an example of an actual measurement, and finally we shall add some comments, mainly precautions and reservations.
214 citations
TL;DR: New electron microscopic immunocytochemical findings in the laboratory suggest that the origin of alkaline phosphatase-positive bone matrix vesicles is polarized to the mineral-facing side of osteoblasts and may be concentrated near the intercellular junctions of human embryonic osteoblasting.
210 citations
TL;DR: Data indicate that both cells derive from the resting cell zone and adjacent growth zone of rat costochondral cartilage retain differential expression of phenotype in culture and that one expression of this phenotype is production of specific extracellular matrix vesicles.
188 citations
References
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TL;DR: It is suggested that matrix vesicles are derived from cells and that they may play a role in initiating calcification at the epiphysis.
Abstract: Vesicles have been identified within the cartilage matrix of the upper tibial epiphyseal plate of normal mice. They were seen at all levels within the plate and usually did not appear to be in contact with cartilage cells. Vesicles were concentrated within the matrix of the longitudinal septa from the proliferative zone downward. They varied considerably in size (∼300 A to ∼1 µ) and in shape. They were bounded by unit membranes, and contained materials of varying density including, rarely, ribosomes. A close association was demonstrated between matrix vesicles and calcification: in the lower hypertrophic and calcifying zones of the epiphysis, vesicles were found in juxtaposition to needle-like structures removed by demineralization with ethylenediaminetetraacetate and identified by electron diffraction as hydroxyapatite and/or fluorapatite crystal structure—the former being indistinguishable from the latter for most cases in which electron diffraction methods are employed. Decalcification also revealed electron-opaque, partially membrane-bounded structures within previously calcified cartilage of the epiphyseal plate and underlying metaphysis which corresponded in size and distribution to matrix vesicles. It is suggested that matrix vesicles are derived from cells and that they may play a role in initiating calcification at the epiphysis.
951 citations
TL;DR: Robison was able to study for two years in Leipzig in the kdbordtories of Professor Hantz as mentioned in this paper, where he obtained a scholarship to attend the University of Nottingham.
Abstract: Robert Robison (Fig. 1) was born in 1883 in Newark-on-Trent. He attended the University College. Nottingham. He began his career in research before he obtained his initial degree. Having obtained a scholarship, Robison was able to study for two years in Leipzig in the kdbordtories of Professor Hantz
706 citations
TL;DR: ATPase and ATP-dependent calcium ion concentration was studied with a membrane fraction isolated from homogenized rabbit skeletal muscle by differential centrifugation, indicating that it consists mainly of resealed tubules and vesicles of the endoplasmic reticulum.
Abstract: ATPase and ATP-dependent calcium ion concentration was studied with a membrane fraction isolated from homogenized rabbit skeletal muscle by differential centrifugation. Electron micrographs of the fraction indicate that it consists mainly of resealed tubules and vesicles of the endoplasmic reticulum. The up-to-1400-fold concentration of calcium in this fraction might be explained by proposing the existence of an energy-requiring system for the transport of calcium ions into the tubules or vesicles.
672 citations
TL;DR: Cartilage at an early stage of calcification, as shown by an electron microscope study of costochondral junctions of 1-month-old guinea pigs, and of proximal tibial—distal femoral epiphyses of 3-day-old rats, is characterized by the formation of osmiophilic, PAS-reactive, roundish bodies, having amorphous structure and pericellular distribution.
600 citations
473 citations