Nanotechnology Targeting Novel CD154:CD11b Interactions for Transplant Tolerance

摘要/概要 已知阻断CD 40-CD 154相互作用是抑制同种异体反应性T细胞增殖的高效手段。 在某些条件下诱导鼠和非人的移植耐受 灵长类动物模型。然而，这种治疗策略的潜力，有一个变革性的影响， 移植结果尚未实现。CD 154阻滞剂与不良反应相关， 在早期的临床试验中发现了高凝状态，促使治疗靶向CD 40作为替代疗法。 然而，CD 40阻滞剂在最近的临床试验中由于疗效不足而失败。因此，我们力求 确定是否存在生物学解释，以解释观察到的阻断CD 40的劣效性， 在2020年的一项研究中，我们报告说，CD 11b是一种 同种异体免疫期间CD 154的第二受体，通过其信号传导被抗CD 154阻断 抗CD 40试剂。我们发现，CD 154：CD 11b相互作用在局部发挥作用， 同种异体移植物，以增强供体反应性CD 8 + T细胞浸润和加速同种异体移植物排斥。此外，新 初步数据显示，CD 154而不是CD 40阻断导致移植物特异性Foxp 3+的产生， iTreg，表明加入CD 154：CD 11b阻断剂可在CD 154：CD 11b抑制的情况下促进iTreg的产生。 抗CD 40抗体。在这个提议中，我们将把这些发现转化为NHP同种异体肾移植模型， 阐明CD 154：CD 11b阻断在移植耐受中的作用，并测试一种新的纳米粒。 更好地靶向CD 154：CD 11b相互作用并与抗CD 40协同促进移植的策略 体内耐受性在第一个目标中，我们将阐明CD 154：CD 11b阻断的机制。 有助于抑制同种免疫和诱导Foxp 3 + Treg，使用新技术鉴定 并追踪NHP中的同种异体反应性效应细胞和调节性T细胞，并将使用MIBI-TOF和转录组学技术， 研究阻断CD 154：CD 11b相互作用对免疫结构的影响的方法， 同种异体移植物内的T细胞、DC和巨噬细胞/单核细胞的转录组学谱。在第二个目标中，我们有 开发了一种新的纳米颗粒，它被一种特异性的肽抑制剂所包裹，这种肽抑制剂可以阻止CD 154：CD 11b 约束力利用尖端的纳米技术来阻止这种相互作用，而不是单克隆抗体， 用单独的免疫调节剂对纳米颗粒进行生物工程改造的能力的明显优点是， “有效载荷”，以进一步促进宽容。考虑到CD 154阻断剂已证实的诱导长期， 我们的总体假设是，结合新的CD 154：CD 11b阻断剂， 与抗-CD 40的纳米颗粒将导致移植耐受的建立。

Abstract/ Summary Blockade of CD40-CD154 interactions is known to be a highly effective means of inhibiting alloreactive T cell responses and under some conditions inducing transplantation tolerance in both murine and non-human primate models. However, the potential of this therapeutic strategy to have a transformative impact on transplantation outcomes has yet to be realized. CD154 blockers were associated with adverse hypercoagulability in early clinical trials, instigating the therapeutic targeting of CD40 as an alternative therapy. However, CD40 blockers have failed in recent clinical trials due to insufficient efficacy. We therefore sought to determine if there is a biological explanation underlying the observed inferiority of blocking CD40 as compared to blocking CD154, in order to then devise ways to overcome it. In a 2020 study, we reported that CD11b is a second receptor for CD154 during alloimmunity, signaling through which is blocked by anti-CD154 reagents but not anti-CD40 reagents. We showed that CD154:CD11b interactions function locally within the allograft to enhance donor-reactive CD8+ T cell infiltration and accelerate allograft rejection. In addition, new preliminary data show that CD154 but not CD40 blockade results in the generation of graft-specific Foxp3+ iTreg, suggesting that the addition of CD154:CD11b blockade may boost iTreg generation in the context of anti-CD40. In this proposal, we will translate these findings into an NHP allogeneic renal transplant model to elucidate the role of CD154:CD11b blockade in transplantation tolerance, and to test a novel nanotherapeutic strategy to better target CD154:CD11b interactions and synergize with anti-CD40 in promoting transplantation tolerance in vivo. In the first Aim, we will elucidate the mechanisms by which CD154:CD11b blockade contributes to the inhibition of alloimmunity and the induction of Foxp3+ Treg, using novel techniques to identify and track alloreactive effector and regulatory T cells in NHP, and will use MIBI-TOF and transcriptomic approaches to interrogate the effects of blocking CD154:CD11b interactions on the immune architecture and transcriptomic profile of T cells, DC, and macrophage/monocytes within allografts. In the second Aim, we have developed a novel nanoparticle that is coated with a specific peptide inhibitor that prevents CD154:CD11b binding. Utilizing cutting edge nanotechnology to block this interaction, instead of a monoclonal antibody, offers the distinct advantage of the ability to bioengineer the nanoparticle with a separate immunomodulatory “payload” to further promote tolerance. Given the demonstrated ability of CD154 blockade to induce long-term, durable tolerance in NHP, our overall hypothesis is that combining the novel CD154:CD11b blocking nanoparticle with anti-CD40 will result in the establishment of transplantation tolerance.