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A tolerogenic semimature dendritic cells induce effector T-cell hyporesponsiveness by activation of antigen-specific CD4+CD25+ T regulatory cells that promotes skin allograft survival in mice.

Department of Organ Transplantation, The First Affiliated Hospital of Sun Yat-sen University, Guang Zhou, China.
Cellular Immunology (Impact Factor: 1.87). 01/2010; 261(1):69-76. DOI: 10.1016/j.cellimm.2009.11.003
Source: PubMed

ABSTRACT Semimature dendritic cells (smDCs) can induce autoimmune tolerance by activation of host antigen-specific CD4(+)CD25(+) regulatory T (Treg) cells. We hypothesized that donor smDCs injected into recipients would induce effector T-cell hyporesponsiveness by activating CD4(+)CD25(+)Treg cells, and promote skin allograft survival. Myeloid smDCs were derived from C57BL/6J mice (donors) in vitro. BALB/c mice (recipients) were injected with smDCs to generate antigen-specific CD4(+)CD25(+)Treg cells in vivo. Allograft survival was prolonged when BALB/c recipients received either C57BL/6J smDCs prior to grafting or C57BL/6J smDC-derived CD4(+)CD25(+)Treg cells post-grafting, and skin flaps from these grafts showed the highest IL-10 production regardless of rapamycin treatments. Our findings confirm that smDCs constitute an independent subgroup of DCs that play a key role for inducing CD4(+)CD25(+)Treg cells to express high IL-10 levels, which induce hyporesponsiveness of effector T cells. Pre-treating recipients with donor smDCs may have potential for transplant tolerance induction.

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