## 4 Discussion  
Adult stem cells are widely used in regenerative medicine for their multiline and regenerative potential [37]. The study of the properties of mesenchymal stem cells is very important for their properties and their perspective use in regenerative medicine. In this work, we discuss the immunomodulatory properties of MSCs and the effects on lymphocytes proliferation on MSCs. The most commonly used source of mesenchymal stem cells is bone marrow. Later sources of \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Phenotype Expression** & **CD90 [\%]** & **CD44 [\%]** & **CD54 [\%]** & **TLR4 [\%]** & **TLR3 [\%]** & **IL-10 [\%]** \\ \hline \multicolumn{1}{c}{} & & & & & & \\ \multicolumn{1}{c}{} & & & & & & \\ \multicolumn{1}{c}{} & & & & & & \\ \multicolumn{1}{c}{} & & & & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Significant differences of CD44, CD54, and IL-10 between phenotype markers in co-cultured CMSC _Poly (IC)_ and CMSC. Figure 9: Phenotype expression markers co-cultured chorionic mesenchymal stem cells activated with polyinosine: polyctidylic acid CMSCs _Poly (I:C)_ and CMSCs by paired t-test showed differences in the groups CD54 (%) (\(p\) = 0.0000), CD44 (%) (\(p\) = 0.0006), and IL-10 (%) (\(p\) = 0.0000); differences were not confirmed in the CD90 (%) (\(p\) = 0.8662), TLR3 (%) (\(p\) = 0.375200) and TLR4 (%) (\(p\) = 0.0925) groups, t-test. Histograms represent mean \(\pm\) S.E of seven independent experiments. TLR = Toll-like receptor. MSCs were expanded by other tissues, especially fatty tissue. The authors observed a significant reduction in interferon (IFN) gamma production of activated T cells after co-cultivation with human exosomes adipose MSCs fatty tissue [38]. Fetal membrane is a promising source of mesenchymal cells. Chorion was used as a source of MCSs. Unlike embryonic stem cells, chorionic mesenchymal cells can be experimentally used without ethical conflict, in contrast to embryonic stem cells. Sources of perinatal stem cells include umbilical cord blood, the Wharton's Jelly matrix of umbilical cord, amniotic fluid, the amnion and chorion. Perinatal tissues are important sources of stem cells. Perinatal stem cell is a type of cell that partially has the properties of postnatal stem cells and the properties of pluripotent, embryonic stem cells. Chorionic MSCs expressed genes associated with the undifferentiated cells NANOG, OCT4, and REX1 [39]. Due to the narrow ontogenetic relationships with embryonic stem cells, perinatal stem cells have lower immunogenicity. They contain a higher proportion of naive, spontaneous T lymphocytes, a small percentage of NK cells and overall lower immunogenicity. Differences between individual MSCs were observed [40]. The distinct difference in mesenchymal cells from individual sources is their different proliferative activity. Chorionic MSCs have higher proliferative activity compared to bone marrow and adipose tissue MSCs. Lower proliferation potential was recorded only in MSCs isolated from the amniotic membrane [41]. Placenta-derived cells have multilineage differentiation potential similar to MSCs in terms of morphology, cell-surface antigen expression, and gene expression patterns [42]. The immunomodulatory properties of CMSCs are less explored. The study focuses mainly on the effect of CMSCs on lymphocytes as well as monitoring the proliferation of activated lymphocytes via CMSCs. Characteristic features of mesenchymal stem cells isolated from the chorion, phenotype, adherence, and formation of CFU-F were observed. Expression of the major features of CD105+, CD90+, CD73+, CD44+, CD29+, CD54+, CD45-, and CD34- hematopoietic stem cells were also observed. Difference in the expression of these characters depending on the length of cultivation was detected. In the CMSCs primo-culture, the expression of all the mesenchyme features was detected at a lower percentage. The presence of hematopoietic markers was partially observed. In the following passages, the expression of hematopoietic markers was not detected.