Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.
Sci Transl Med. 2011 May 18;3(83):83ra40. doi: 10.1126/scitranslmed.3002099.
Regulatory T cells (T(regs)) manipulated ex vivo have potential as cellular therapeutics in autoimmunity and transplantation. Although it is possible to expand naturally occurring T(regs), an attractive alternative possibility, particularly suited to solid organ and bone marrow transplantation, is the stimulation of total T cell populations with defined allogeneic antigen-presenting cells (APCs) under conditions that lead to the generation or expansion of donor-reactive, adaptive T(regs). Here we demonstrate that stimulation of mouse CD4(+) T cells by immature allogeneic dendritic cells combined with pharmacological inhibition of phosphodiesterase 3 (PDE) resulted in a functional enrichment of Foxp3(+) T cells. Without further manipulation or selection, the resultant population delayed skin allograft rejection mediated by polyclonal CD4(+) effectors or donor-reactive CD8(+) T cell receptor transgenic T cells and inhibited both effector cell proliferation and T cell priming for interferon-γ production. Notably, PDE inhibition also enhanced the enrichment of human Foxp3(+) CD4(+) T cells driven by allogeneic APCs. These cells inhibited T cell proliferation in a standard in vitro mixed lymphocyte assay and, moreover, attenuated the development of vasculopathy mediated by autologous peripheral blood mononuclear cells in a functionally relevant humanized mouse transplant model. These data establish a method for the ex vivo generation of graft-reactive, functional mouse and human T(regs) that uses a clinically approved agent, making pharmacological PDE inhibition a potential strategy for T(reg)-based therapies.
调节性 T 细胞（Tregs）经体外操作后具有作为细胞治疗剂在自身免疫和移植中的应用潜力。虽然可以扩增天然存在的 Tregs，但另一种有吸引力的可能性，特别是适用于实体器官和骨髓移植，是在导致产生或扩增供体反应性、适应性 Tregs 的条件下，用定义的同种异体抗原呈递细胞（APCs）刺激总 T 细胞群体。在这里，我们证明了用未成熟的同种异体树突状细胞刺激小鼠 CD4+T 细胞，结合磷酸二酯酶 3（PDE）的药理学抑制，导致 Foxp3+T 细胞的功能富集。无需进一步操作或选择，所得群体延迟了由多克隆 CD4+效应物或供体反应性 CD8+T 细胞受体转基因 T 细胞介导的皮肤同种异体移植物排斥，并抑制效应细胞增殖和 IFN-γ产生的 T 细胞启动。值得注意的是，PDE 抑制也增强了同种异体 APC 驱动的人 Foxp3+CD4+T 细胞的富集。这些细胞在标准的体外混合淋巴细胞试验中抑制 T 细胞增殖，此外，在功能相关的人源化小鼠移植模型中，减弱了由自体外周血单核细胞介导的血管病变的发展。这些数据建立了一种体外生成同种异体反应性、功能性小鼠和人 Tregs 的方法，该方法使用了一种临床批准的药物，使药理学 PDE 抑制成为基于 Treg 的治疗的潜在策略。
