Introduction. Mesenchymal stem cells (MSCs) are adult stem cells (Pittenger et al., 1999, Zhang et al., 2009) able of self-renewal, with low immunogenicity and immunoregulatory property (Jorgensen et al, 2003, English et al., 2008, Zhang et al., 2009). Dendritic cells (DCs) present in the bone marrow play a crucial role in the instruction of adaptive immunity (Nauta et al., 2006, Zhi-Gang et al., 2012) DC have the unique capacity to stimulate naive and memory T cells (Banchereau et al., 2000, Nauta et al., 2006, Wang et al., 2013). The aim of the present study was to assess the effect of MSCs on DC maturation. Materials and Methods. MSCs were collected from femurs of male Wistar rats. Cells suspension were cultured in DMEM/F12 supplimented with 10% fetal calf serum (FCS), 5% horse serum and 1% antibiotic– antimycotic (Gibco). DCs were prepared from rat bone marrow after red cells lysis and cultured in RPMI 1640 medium (Gibco) supplemented with 10% FCS, 1% antibiotic–antimycotic (Gibco), 10 ng/mL GM-CSF (Sigma), and 5 ng/mL IL-4 (Sigma). MSCs and DCs were cultured for 7d at 37°C. DCs (5x105) were grown in two different conditions: co-culturing with MSCs and 25 ng/ml TNF (I) or without MSCs and 25 ng/ml TNF (Sigma) (II) for 48d. Cell phenotype were characterized by flow cytometry (FACSCanto II) using CD11b, CD44, CD86 (Becton Dickinson) antibodies. Results and Conclusion. After co-culture with MSCs, DC showed a decrease in CD86 expression compared with culture supplemented only with TNF which showed an increase in expression of this marker. Acknowledgements-This work was supported by Forerunner Federation