*3.5. Decrease in Proportion of Myeloid Derived Suppressor Cells in Spleens of Mice Immunized with MSCs*

Using flow cytometry, we compared the number of splenocytes from immunized mice that express CD11b+Gr-1+ markers of MDSCs and do not express CD11c marker of dendritic cells (DC) (Figure 5a). An almost twofold decrease in the relative content of MDSCs in groups 1 and 2 compared with groups 3 and 4 was found (*p* = 0.007 and 0.015, respectively) (Figure 5b). The content of CD11c+ dendritic cells varied from 6.3 to 7.5% and did not differ between groups (results not shown, *p* > 0.05). The lowest MDSCs to dendritic cells ratio was observed in the spleens of mice of group 1 (*p* = 0.003 compare to control) (Figure 5c).

**Figure 5.** A comparative analysis of the proportion of myeloid derived suppressor cells in spleens of immunized mice. Splenocytes from the immunized mice were stained with anti-CD11c, anti-CD11b, and anti-Gr1 antibodies and analyzed by flow cytometry. Representative dot plots (**a**) and mean values (**b**) of the number of MDSC expressing CD11b and Gr1, and negative for the marker of DC (CD11c) are shown, in the percentages; (**c**) the MDSCs to dendritic cells (DC) ratio. Values on each diagram are means ± SD of three independent analysis, and each of them was performed in triplicate. \* *p* < 0.05 compared to Gr3 and Gr4 (**b**) or compared to the control Gr4 (**c**).
