| Abstrakt: |
The effect of cell culture conditions on numerical and structural karyotypic variability was investigated in two Indian muntjac skin fibroblast "markerless" cell lines, M and MT. The cells cultivated on the substrate consisting of extracellular matrix proteins (ECM), synthesized by human mesenchymal stem cells (SC5-MSC). The character of cell distribution for chromosome number of cell line M changed after cultivation for 1 and 4 days as compared to control cells, which were cultured on hydrophilic surface without ECM-coating. These changes involve a significant decrease in frequency of cells with modal numbers of chromosomes and an increase in frequency of cells with lower chromosome numbers. Many new types of additional structural variants of the karyotype (SVK) appear. MT cell line, differing from M line in the number of homologous chromosomes, demonstrated similar with M line the character of cell distribution for chromosome number only for 1 day after cultivating on the ECM-substrate, but not after 4 days in the same culture conditions, no difference from the control cells was observed. The observed alterations seem to be due to disturbances in correct chromosome segregation process, which were caused by abrupt shift in the cell culture conditions. The analysis of the structural karyotypic variability revealed significant increase in frequency of chromosomal aberrations in M cell line for 1 and 4 days in culture on the ECM-substrate as compared to the control cells. The frequency of dicentric chromosomes (telomeric associations) was increased and constituted more than 50% of all chromosome aberrations. No increase in frequency of chromosome aberrations was observed for MT cells cultured in the same conditions. The obtained results show that the cell lines of the same origin but of different karyotypic structure react to substrate in a different way. In contrast to M line, in MT line a fast normalization of numerical karyotypic characteristics and no enhancement of structural karyotypic variability takes place. This provides a possibility to cultivate MT cell on the given protein substrate maintaining a balanced karyotypic structure characteristic of MT cell line. |
