Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmic and Visual Science Key Lab, Beijing, China.
Hum Immunol. 2012 Nov;73(11):1061-7. doi: 10.1016/j.humimm.2012.08.014. Epub 2012 Aug 29.
Natural CD4(+)CD25(+) regulatory cells (nTregs) have been implicated in maintaining peripheral immune tolerance. This study aims to test whether immunotherapy using in vitro-expanded Treg (iTregs) could suppress allograft rejection in corneal transplantation model.
Natural CD4(+)CD25(+) T cells were freshly purified from naïve mice and expanded in vitro by culturing with anti-CD3/CD28-coated Dynabeads, interleukin (IL)-2 and transforming growth factor (TGF-β1). Suppression ability of iTregs was assayed by co-culturing with CD4(+)CD25(-) T cells (Teff) in vitro and by targeting corneal allograft rejection in vivo. Tracking of iTreg after adoptive transfer in vivo were examined by CFSE labeling.
Natural Treg cells were expanded by culturing with anti-CD3/CD28-coated Dynabeads in the presence of IL-2 and TGF-β1. Compared with nTregs, iTregs had similar expression of CD62L, and PD- L1, lower expression of CD69, higher levels of PD-1, CD25, and Foxp3. iTreg cells exerted stronger suppression function than natural Treg cells when cocultured with CD4(+)CD25(-) T cells in vitro and prevented fully MHC-mismatched corneal allograft rejection. Survival of iTreg cells could suppress alloimmune reaction and most prone to migrate to graft draining LNs and spleens. Moreover, maintaining CD25 expression on iTregs was indicative for preservation of allosuppression.
Therapeutic use of in vitro-expanded CD4(+)CD25(+) T cells may be a effective and safe tool for controlling allograft rejection and may help induce allograft tolerance.
天然 CD4(+)CD25(+)调节性细胞（nTregs）被认为参与维持外周免疫耐受。本研究旨在测试体外扩增的调节性 T 细胞（iTregs）免疫疗法是否可抑制角膜移植模型中的同种异体移植物排斥反应。
从幼稚小鼠中新鲜纯化天然 CD4(+)CD25(+)T 细胞，并用抗 CD3/CD28 包被的 Dynabeads、白细胞介素（IL）-2 和转化生长因子（TGF-β1）在体外扩增。通过体外共培养 CD4(+)CD25(-)T 细胞（Teff）和体内靶向角膜同种异体移植排斥反应来检测 iTregs 的抑制能力。通过 CFSE 标记来检测体内过继转移后 iTreg 的追踪。
天然 Treg 细胞在用抗 CD3/CD28 包被的 Dynabeads 培养时，在 IL-2 和 TGF-β1 的存在下扩增。与 nTregs 相比，iTregs 具有相似的 CD62L 表达和 PD-L1 表达，较低的 CD69 表达，较高的 PD-1、CD25 和 Foxp3 水平。与体外共培养的 CD4(+)CD25(-)T 细胞相比，iTreg 细胞具有更强的抑制功能，并可防止完全 MHC 错配角膜同种异体移植物排斥反应。iTreg 细胞的存活可抑制同种免疫反应，且最易迁移至移植物引流 LNs 和脾脏。此外，维持 iTreg 上的 CD25 表达提示保持了同种异体抑制作用。
体外扩增的 CD4(+)CD25(+)T 细胞的治疗应用可能是控制同种异体移植物排斥反应的有效且安全的工具，并可能有助于诱导同种异体耐受。
