Functional analysis and the molecular mechanism of CCR5 in the CTL induction.

1.免疫突触中的趋化因子受体调节抗原识别的敏感性：CCR 5主要在静息记忆T细胞上表达，其表达在活化T细胞上增强。尽管CCR 5被认为是HIV的共受体，但已经提出CCR 5除了趋化性之外还具有作为体外白细胞活化的共刺激分子的功能。为了扩展这一想法，我们已经通过评估BRET（生物发光共振能量转移）信号表明，在TCR刺激后，CCR 5在免疫突触中积累并实际上被激活。此外，CCR 5拮抗剂TAK-779通过CD 3和CD 28包被平板强烈抑制人CD 8 +T细胞增殖，并在TCR刺激后通过Rapt强烈抑制LFA-1由内而外的信号传导。我们通过建立CCR 5和CXCR 3双基因敲除小鼠，证实了CCR 5和CXCR 3在体内作为T细胞的共刺激分子发挥作用。总之，CD 8 +T细胞上的CCR 5和CXCR 3具有与T细胞受体介导的信号的共刺激信号或增强信号，以通过免疫突触中的Rapl调节LFA-1活化。这些发现解释了最近报道的CCR 5delta 32突变受者完全接受肾移植的机制。2.通过靶向趋化因子阻断GVHD和选择性诱导GVL/T的方法的开发：在急性GVHD模型中，供体CD 8 T细胞在次级淋巴器官中增殖和分化，并在隐窝处诱导肠上皮细胞凋亡。令人惊讶的是，针对Fractalkine/MAdCAM-1的中和抗体抑制肠损伤。将肿瘤细胞P815（H-2_d）注射入BDF-1（H-2_b）中<bd>，并将来自C57 BL/6（H-2_b）的脾细胞转移至受体小鼠，观察到受体存活的延长，保留了GVL效应。因此，我们提出了通过靶向CX 3CR-1-Fractalkine和a4 b7-MadCAM-1保持GVL/T效应来治疗GVHD。

1. Chemokine receptors in the immunological synapse regulate the sensitivity of antigen recognition : CCR5 is predominantly expressed on resting memory T cells of which expression is enhanced on activated T cells. Although CCR5 is known as, a coreceptor of HIV, it has been suggested that CCR5 has also a function as a costimulatory molecule for leukocyte activation in vitro other than chemotaxis. To extend this idea, we have shown that CCR5 accumulated and actually was activated in the immunological synapse after TCR stimulation by evaluating BRET (Bioluminescence Resonance Energy Transfer) signals. Furthermore, a CCR5 antagonist, TAK-779 strongly inhibited human CD8+T cell proliferation by CD3 and CD28 coated plates and also LFA-1 inside-out signaling through Rapt after TCR stimulation. We confirmed that CCR5 and CXCR3 function as costimulatory molecules of T cells in vivo by developing double CCR5 and CXCR3 knockout mouse. Taken together, CCR5 and CXCR3 on CD8+T cells have a costimulatory signal or boosting signal with T cell receptor mediated-signal to regulate LFA-1 activation through Rapl in the immunological synapse. These findings explain a mechanism of recent report describing complete acceptance of kidney transplants in recipients with CCR5delta32 mutation.2.Blockade of GVHD by targeting chemokines and development of a way to selectively induce GVL/T : In an acute GVHD model, donor CD8T cells proliferated and differentiated in the secondary lymphoid organs and apoptosis of intestinal epithelium was induced at the crypts. Surprisingly, neutralizing antibodies against Fractalkine/MAdCAM-1 inhibited intestinal injury. When tumor cells P815 (H-2^d) were injected into BDF-1 (H-2^<bd>) and the splenocytes from C57BL/6 (H-2^b) were transferred to recipient mice, elongation of the survival of recipients was observed preserving GVL effect. Thus we propose a therapy for GVHD by targeting CX3CR-1-Fractalkine and a4b7-MadCAM-1 keeping GVL/T effect.