Abstract
Purpose: :
Mesenchymal stromal cells (MSC) are non-hemopoietic cells with the capacity to self-renew and differentiate into various cell lineages of mesenchymal origin. Recently, the immune regulatory potential of MSC has been focused on. By the one hand, amniotic membrane (AM) mesenchymal cells (AM-MSC) are capable of inducing allogenic T cell suppression, as well as promoting a tolerogenic microenvironment; by the other hand, mesenchymal stem cells obtained from limbal murine tissue possess immunomodulatory properties and inhibit proinflammatory immune reactions. The aim of this study was to determine the immunosuppressive characteristics of two different mesenchymal populations isolated from human AM and limbal tissues.
Methods: :
Phenotypic analysis of AM-MSC and L-MSC were performed by means of molecular and flow cytometry assays. TCR stimulated peripheral blood mononuclear cells were co-cultured with either AM-MSC or L-MSC on a transwell system and T cell proliferation was documented by flow cytometry. ELISA method was performed to detect IL-10 and TGFbeta immunosuppressive cytokines from the culture supernatants.
Results: :
Herein, we described that both AM- or L-MSC cell populations in vitro-expanded have similar phenotypic characteristics in comparison with those described to bone marrow mesenchymal stromal cells. In addition, AM- or L-MSC co-cultured in a transwell system with peripheral blood mononuclear cells stimulated with anti-CD3/CD28 are capable to suppress TCR-engagement lymphocyte proliferation, which can be reverted using anti-TGFbetaRII neutralizing antibodies. Moreover, TGFbeta1 was constitutively secreted by AM- or L-MSC as determined by ELISA. Thus, TGFbeta1 secreted by Amniotic Membrane as well as Limbal Mesenchymal Stromal Cells is able to suppress T cell proliferation.
Conclusions: :
Taken together these results, explain in part the immunosuppressive features of these two cell populations obtained from two different human tissues.
Keywords: cornea: basic science • cytokines/chemokines • cornea: stroma and keratocytes