Author/Editor     Koselj, Samo
Title     Vpliv kalcijevih ionov na morfologijo in metabolizem človeških artikularnih hondrocitov
Translated title     The influence of calcium ions on the morphology and metabolism of human articular chondrocytes
Type     monografija
Place     Ljubljana
Publisher     Medicinska fakulteta
Publication year     2000
Volume     str. 60
Language     slo
Abstract     In order to determine the phenotype (presence or absence of the collagen type I, collagen type II and aggrecan) of human articular chondrocytes in monolayer culture, we introduced the indirect fluorescent antibody procedure. We found that cells after four weeks of cultivation synthesize not only collagen type I, but also cartilage specific collagen type II and aggrecan. In order to clarify the influence of clacium ions on the morphology of human articular chondrocytes, we observed the effect of medium with calcium ions, medium where the calcium ions were depleted by EGTA and medium with ionomycin, on the morphology of these cells. Our results demonstrate the calcium ions dependence of morphology in human articular chondrocytes. The presence of calcium ions favours flattened cell shape. On the other hand the absence of calcium ions favours round cell shape. After monolayer trypsinization extracellular calcium ions are required for a rapid shape change of cells from round to flatten. Elevated concentration of intracellular calcium ions slows-down this process. In addition, we have found that transition of cells from flatten to round shape in the medium without calcium ions is accompanied by the formation of a microvillous surface and numerous cytoplasmic vacuoles. Finally the dot-blot technique was used to determine the effect of extracellular calcium ions on the expression of collagen type I, collagen type II and aggrecan by chondrocytes in monolayer culture. We found that the presence of calcium ions jn the medium is necessary for intensive production of all three metabolites. The absence of calcium ions markedly reduce the synthesis of both collagens and aggrecan.
Descriptors     CELLS, CULTURED
COLLAGEN
CALCIUM
CARTILAGE, ARTICULAR
PHENOTYPE
CYTOSOL
FLUORESCENT ANTIBODY TECHNIQUE