induction of t regulatory subsets from naïve cd4+ t cells after exposure to breast cancer adipose derived stem cells

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.