Chemokines and T Cell Recruitment in High Risk Corneal Allograft Rejection

摘要 “高危”血管化角膜床受者的角膜移植存活率很低， 免疫排斥我们的假设是这些移植物的命运与其他实体器官相似 血管化同种异体移植物，需要积极的全身免疫抑制，以改善 生存同种异体移植物的排斥反应是通过协调募集和浸润的 同种异体特异性T细胞。最近，研究固体免疫排斥反应的研究 血管化的同种异体器官移植表明，在移植后早期诱导选择性趋化因子， 手术后的移植部位是T细胞进入排斥反应的最佳募集所必需的。 同种异体移植我们的数据表明，T细胞向移植物中的募集在高风险的排斥反应中也是至关重要的。 血管化角膜移植这与中性粒细胞化学引诱物的早期产生有关 CXCL 1/KC和T细胞趋化因子的晚期上调：CXCL 9/Mig（由CXCL 9/Mig诱导的单核因子） IFN-γ）和CXCL 10/IP 10（IFN-γ诱导蛋白）。尽管CXCL 1/KC的体内中和作用 结果增加了移植物存活，我们最近的数据表明，CXCL 10/IP 10的中和导致了移植物存活率的增加。 更快和更强大的拒绝。在本申请中，我们将测试一个假设，即高风险血管化 角膜就像一个血管化的实体器官移植。CXCL 1/KC的早期产生至关重要 对于募集同种特异性效应物所必需的T细胞化学引诱物的晚期诱导，或 调节性CD 4 T细胞进入移植物。本申请中提出的实验的总体目标是 了解血管化角膜环境如何调节早期CXC趋化因子的产生 以及将引发的同种异体特异性效应细胞和调节性T细胞募集到移植物中以介导 排斥反应在目标1中，我们将使用一种追踪抗原特异性T细胞的新系统进行测试， 监测同种异体特异性T细胞的启动，并测试这是否被高危血管化角膜同种异体移植物改变， 这样就有更多具有不同表型的T细胞被优化用于募集。在目标2中， 我们将鉴定CXCL 1/KC的细胞来源，并测试CXCL 1/KC如何诱导T细胞的晚期产生。 通过增加产生IFN-γ的CXCR 2+细胞的浸润来诱导细胞化学引诱物。实验目的 3将使用中和抗体和CXCL/9/Mig缺陷的小鼠来测试这种T细胞 化学引诱物负责增加T细胞向移植物中的募集。我们还将利用 使用荧光标记的效应和调节性T细胞的新型动物模型来测试移植物内 趋化因子改变它们的募集和移植结果。本文中描述的实验结果 该提案将确定新的治疗试剂和抑制策略的发展目标 T细胞浸润到高风险同种异体移植物中。这将最终提高移植物存活率，同时降低移植物的存活率。 依赖于目前可用的普遍的和使人衰弱的免疫抑制方案。

ABSTRACT The survival rate of corneal allografts in "high risk" vascularized corneal bed recipients is poor due to immune rejection. Our hypothesis is that these grafts are similar to the fate of other solid organ vascularized allogeneic grafts that require aggressive systemic immune-suppression to improve survival. The rejection of allografts is mediated through the coordinated recruitment and infiltration of allo-specific T cells. Most recently, studies investigating the immunological rejection of solid vascularized organ allotransplants have shown that the early induction of selective chemokines at the site of transplantation after surgery is required for the optimal recruitment of T cells into rejecting allografts. Our data shows that recruitment of T cells into the graft is also critical in rejection of high risk vascularized corneal allografts. This correlates to the early production of the neutrophil chemoattractant CXCL1/KC and late up-regulation of the T cell chemoattractants: CXCL9/Mig (monokine induced by IFN-¿) and CXCL10/IP10 (IFN-¿-inducible protein). Although the in vivo neutralization of CXCL1/KC results in increased graft survival, our recent data shows that neutralization of CXCL10/IP10 causes a faster and robust rejection. In this application we will test the hypothesis that a high risk vascularized cornea behaves like a vascularized solid organ transplant. The early production of CXCL1/KC is crucial to the late induction of T cell chemoattractants necessary for the recruitment of allo-specific effector or regulatory CD4 T cells into the graft. The overall goal of the experiments proposed in this application is to understand how the vascularized corneal environment regulates early CXC chemokine production and the recruitment of primed allo-specific effector and regulatory T cells into the graft to mediate rejection reactions. In Aim 1, we will test using a novel system of tracking antigen specific T cells, to monitor allo-specific T cells priming and test this is altered by high risk vascularized corneal allografts in such a way that there are more T cells with a different phenotype optimized for recruitment. In Aim 2, we will identify the cell source of CXCL1/KC and test how CXCL1/KC induces the late production of T cell chemoattractants by increasing infiltration of CXCR2+ cells that produce IFN-¿. Experiments in Aim 3 will use neutralizing antibodies and mice deficient in CXCL/9/Mig to test that this T cell chemoattractant is responsible for the increased recruitment of T cells into the graft. We will also utilize novel animal models with fluorescently labeled effector and regulatory T cells to test how intragraft chemokines alter their recruitment and graft outcome. The results from experiments described in this proposal will identify targets for the development of novel therapeutic reagents and strategies to inhibit T cell infiltration into high risk allografts. This will ultimately improve graft survival while decreasing the dependence on the generalized and debilitating immunosuppressive regimens currently available.