Mahboobeh Razmkhah; Nadieh Abedi; Ahmad Hosseini; Mohammad Taghi Imani; Abdol-Rasoul Talei; Abbas Ghaderi
Volume 12, Issue 1 , March 2015, , Pages 1-15
Abstract
Background: Adipose derived stem cells (ASCs) provoke the accumulation and expansion of regulatory T cells, leading to the modulation of immune responses in tumor microenvironment. Objective: To assess the effect of tumoral ASCs on the trend of regulatory T cells differentiation. Methods: Peripheral ...
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Background: Adipose derived stem cells (ASCs) provoke the accumulation and expansion of regulatory T cells, leading to the modulation of immune responses in tumor microenvironment. Objective: To assess the effect of tumoral ASCs on the trend of regulatory T cells differentiation. Methods: Peripheral blood naïve CD4+ T cells were co-cultured with ASCs derived from breast cancer or normal breast tissues. In separate cultures peripheral blood naïve CD4+ T cells were exposed to the culture supernatants of ASCs. Results: Generation of CD4+CD25+Foxp3+ and CD4+CD25- Foxp3+ Treg subsets was observed after coculture of naïve CD4+ T cell with either ASCs or the related supernatant. The percentage of CD4+CD25+Foxp3+ cells increased after exposing naïve CD4+ T cells to both ASCs and their supernatants while augmentation of CD4+CD25-Foxp3+ subset mostly depended on the presence of ASCs. Similarly, upregulation of FoxP3 molecule was more significant in condition of cell to cell contact. IL-4 and IL-10 were up-regulated in the cocultured naïve CD4+ T cells after exposure to ASCs/supernatant while IFN-γ was down-regulated in the presence of ASCs. Conclusion: Accordingly, ASC may act as one of the major players in tumor site with immunomodulatory effects, which may mostly be carried out through direct cellcell interaction.
Neda Mousavi Niri; Mansooreh Jaberipour; Mahboobeh Razmkhah; Abbas Ghaderi; Mojtaba Habibagahi
Volume 6, Issue 4 , December 2009, , Pages 186-194
Abstract
Background: Several studies have demonstrated the immunosuppresive effects of mes-enchymal stem cells (MSCs) in allogeneic or mitogenic interactions. Cell-cell contact inhibition and secretion of suppressive soluble factors have been suggested in this re-gard. Objective: To investigate if adipose derived ...
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Background: Several studies have demonstrated the immunosuppresive effects of mes-enchymal stem cells (MSCs) in allogeneic or mitogenic interactions. Cell-cell contact inhibition and secretion of suppressive soluble factors have been suggested in this re-gard. Objective: To investigate if adipose derived MSCs could inhibit Jurkat lym-phoblastic leukemia T cell proliferation during coculture. Methods: Adherent cells with the ability of cellular growth were isolated from normal adipose tissues. Initial charac-terization of growing cells by flow cytometry suggested their mesenchymal stem cell characteristics. Cells were maintained in culture and used during third to fifth culture passages. Jurkat or allogeneic peripheral blood mononuclear cells (PBMCs) were la-beled with carboxy fluorescein diacetate succinimidyl ester and cocultured with increas-ing doses of MSCs or MSC culture supernatant. Proliferation of PBMCs or Jurkat cells under these conditions was assessed by flow cytometry after 2 and 3 days of coculture, respectively. Results: Results showed the expression of CD105, CD166 and CD44, and the absence of CD45, CD34 and CD14 on the surface of MSC like cells. Moreover, ini-tial differentiation studies showed the potential of cell differentiation into hepatocytes. Comparison of Jurkat cell proliferation in the presence and absence of MSCs showed no significant difference, with 70% of cells displaying signs of at least one cell division. Similarly, the highest concentration of MSC culture supernatant (50% vol/vol) had no significant effect on Jurkat cell proliferation (p>0.6). The same MSC lots significantly suppressed the allogeneic PHA activated PBMCs under similar culture conditions. Conclusion: Using Jurkat cells as a model of leukemia T cells, our results indicated an uncertainty about the suppressive effect of MSCs and their inhibitory metabolites on tumor or leukemia cell proliferation. Additional systematic studies with MSCs of differ-ent sources are needed to fully characterize the immunological properties of MSCs be-fore planning clinical applications.