title: The Immunomodulatory Effect of Bone-Marrow Mesenchymal Stem Cells on Expression of TLR3 and TLR9 in Mice Dendritic Cells.
abstract: BACKGROUND
  Mesenchymal stem cells (MSCs) are multipotent cells with immunomodulatory effect on immune cells including dendritic cells (DCs). DCs are the most potent antigen-presenting cells (APC). MSCs have been found to modulate both differentiation and function of DCs. DCs express a broad range of Toll-like receptors (TLR), which play a critical role in DCs maturation and function.
  
  
  OBJECTIVE
  To evaluate expression level of TLR3 and TLR9 transcripts in DCs following treatment with MSCs supernatant.
  
  
  METHODS
  MSCs and DCs were derived from adult BALB/c mice bone marrow and spleen, respectively. MSCs supernatant was harvested following 24, 48, and 72 hours. Isolated DCs were treated with MSCs supernatant and incubated for 24 and 48 hours. TLR3 and TLR9 transcript levels were evaluated using real-time PCR.
  
  
  RESULTS
  The results showed that 48 and 72 hours MSCs supernatant significantly decreased the expression of TLR3 in DCs following 24 and 48 hours incubation in comparison with untreated cells (p<0.01). Moreover, 48 hours of treatment with 24, 48 and 72 hours MSCs supernatant significantly decreased TLR9 transcript level (p<0.05).
  
  
  CONCLUSIONS
  TLR3 and TLR9 mRNA expression decreases in DCs after incubation with MSCs culture supernatant. This confirms the immunomodulatory role of MSCs in cell-base therapy.
authors.affiliation: Department of Biology, Science and Research Branch, Islamic Azad University, Fars, Iran; Department of Biology, Faculty of Science, Shiraz Branch, Islamic Azad University, Shiraz, Iran.
authors.forename: L
authors.initials: L
authors.lastname: Sadeghi
authors.affiliation: Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: M H
authors.initials: MH
authors.lastname: Karimi
authors.affiliation: Autoimmune Disease Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: E
authors.initials: E
authors.lastname: Kamali-Sarvestani
authors.affiliation: Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
authors.forename: N
authors.initials: N
authors.lastname: Azarpira
authors.affiliation: Department of Biology, Islamic Azad University, Kazerun Branch, Kazerun, Iran.
authors.forename: M
authors.initials: M
authors.lastname: Shariati
keywords: Antigen-presenting cells; Dendritic cell; Immunomodulation; Mesenchymal stromal cells; Pathogen-associated molecular pattern molecules; Receptors; Toll-like receptors; pattern recognition