Mesenchymal stem cells stand in the focus of interest of a lot of medicine branches. Our study is focused on their immunomodulatory properties.
We tested the influence of their presence on nonspecific activation of lymphocytes with phytohemagglutinin (PHA) during the lymphocyte transformation test. Adding of MSC into the cultivation medium significantly decreased the level of lymphocyte activation, which was measured by the cell-cycle analysis by flow cytometry.
The number of activated cells in the G2/M phase was decreased by 19 % (median, p{0,01). Insignificant proliferation caused by MSC alone was detected in the culture of non-stimulated lymphocytes - increase of proliferating lymphocytes by 0,9 % (ns).
Monitoring changes in cultures we watched increased viability in cultures with added MSC. The level of fragmented DNA in these samples was by 2,3 % lower (p=0,029) than in the samples without MSC.
The results confirm low immunogenicity of MSC, their protective effect, their ability to decrease lymphocyte activation and support inducing of immunotolerance. MSC may become a new basis for new medical approaches to some immunopathological states (autoimmune disorders, GVHD etc.).