[Comparative characteristics of mesenchymal stem cell lines derived from bone marrow and muscle of limb of early human embryo].

In this work, we have carried out a comparative analysis of the characteristics of mesenchymal stem cell lines isolated from different tissues of 5-6-weeks homan embryo: bone marrow (line FetMSC) and muscle of limb (line M-FetMSC). The basic characteristics of these lines were obtained at the 6th passage. Average population doubling time was 33.0 ± 1.4 h (FetMSC) and 25.0 ± 0.1 h (M-FetMSC). Growth curves also indicated active proliferation of cells of both lines. Numerical and structural karyotypic analysis showed that both lines have a normal karyotype: 46, XY. In order to determine the status of the lines, cell surface markers were analyzed by flow cytometry. The analysis revealed the presence of surface antigens specific for human MSCs, CD44, CD73, CD90, CD105, HLA-ABC, vimentin, and the lack of CD34 and HLA-DR, in both lines. The ability to differentiate into osteogenic, chondrogenic and adipogenic directions has been also shown for both lines. Im- munofluorescence and flow cytometry analysis has detected no expression of the surface antigen TRA-1-60 in both lines, but has revealed high expression of the surface antigen SSEA-4 and low expression of transcription factor Oct-4 characteristic of human embryonic stem cells. In these lines, immunofluorescence analysis has shown the presence of the markers of early differentiation in the derivates of three germ layers characteristic of human embryonic stem cells, which provides significant opportunities for MSC to be useful, in corresponding microenvironments, for repair of tissue injures. Dispite confirming MSC status for FetMSC and M-FetMSC lines, a number of interlinear differences related to growth characteristics and differentiation potential were revealed. Adipogenic differentiatiation potential of M-FetMSC line was reduced compared with FetMSC line. Immunofluorescence analysis showed that, in the process of skeletal-muscle differentiation, Z-disks were revealed only in sarcomeres of M-FetMSC line. These findings suggest the possible influence of different microenvironments in which the cells are in the body before their transfer in vitro.