Rhesus Monkey Dendritic Cells for Transplant Tolerance

描述(由申请人提供)：我们假设稳定未成熟的树突状细胞(DC)可以用于提高耐受性的策略，以促进恒河猴肾移植的供者特异性耐受性。在我们自己和其他人最近的小动物研究中，通过DC疗法实现的器官移植无限期存活与移植血管病变的存在和T调节细胞(Treg)的产生有关，这些T调节细胞渗透到移植物中，使幼稚的受者对排斥反应产生抵抗。在人类志愿者中，只有2.106的未成熟、自体DC促进T细胞耐受以建立AGs模型。我们已经通过在维生素DC和IL-10中繁殖恒河猴单核细胞来源的DC，产生了类似于人类和啮齿动物耐受性DC的“阴性DC疫苗”。同种异体受者系统地输注这些DC，并联合T细胞共刺激抑制，出现T细胞对供者的低反应性，出现CD4+IL-10+T细胞(可能是调节性T细胞)。我们的啮齿动物研究表明，类似的、稳定未成熟的DC与共刺激阻断或雷帕霉素亚治疗疗程相结合，会导致移植物无限期存活。我们有三个特定的目标：目的I：比较不成熟的供体和受体恒河猴DC调节ALLOIMMUNE反应的能力。我们将在体外和体内阐明稳定的未成熟DC如何调节同种异体反应性T细胞反应，特别是Treg的作用，并确定供体-受体DC的比较疗效。目的II：确定耐受性DC在恒河猴肾移植中的疗效及其对潜在免疫调节机制的影响。将比较供者和受者来源的DC在延长移植肾存活时间和调节移植受者的抗供者反应方面的能力。目的III：确定CD40-CD154通路阻断和雷帕霉素在多大程度上增强未成熟DC在促进长期无排斥反应的移植肾存活方面的潜力。我们将在肾移植模型中建立抗GDI 54单抗和“耐受保留”药物雷帕霉素的能力，以增强DC的耐受性，以及它们促进供者特异性耐受的潜力。在NHP器官移植、移植后监测(包括免疫监测)和灵长类动物相关治疗剂的经验方面，有出色的设施和广泛的专业知识来支持和支持这些研究。在临床移植中，对于活体供肾、肝或肺移植，通过输注体外扩增的“耐受性”DC(供者来源的DC或供者同种抗原冲击的受者DC)对预期的移植物受体进行预防性预适应显然是可行的，并可能导致供者特异性耐受。

DESCRIPTION (provided by applicant): We hypothesize that stably-immature dendritic cells (DC) can be employed in tolerance-enhancing strategies to promote donor-specific tolerance to renal allografts in the rhesus macaque. In our own and others' recent small animal studies, indefinite organ graft survival enabled by 'DC therapy', is associated with the absence of transplant vasculopathy and the generation of T regulatory cells (Treg) that infiltrate the graft and confer resistance to rejection in naive recipients. In human volunteers, as few as 2.106 immature, autologous DC promote T cell tolerance to model Ags. We have generated 'negative DC vaccines' that resemble tolerogenic DC in humans and rodents by propagating rhesus monocyte-derived DC in vitamin DC and IL-10. Allogeneic recipients infused systemically with these DC in combination with T cell costimulation blockade, develop T cell hyporesponsiveness to donor, with the emergence of CD4+ IL-10+T cells (putative regulatory T cells). Our rodent studies show that combination of similar, stably-immature DC with costimulation blockade or a sub-therapeutic course of rapamycin results in indefinite graft survival. We have 3 specific aims: AIM I: TO COMPARE THE ABILITY OF MATURATION-RESISTANT, DONOR VERSUS RECIPIENT RHESUS DC TO REGULATE ALLOIMMUNE RESPONSES. We will seek to elucidate both in vitro and in vivo how stably-immature DC regulate alloreactive T cells responses, in particular the role of Treg, and ascertain the comparative efficacy of donor-versus-recipient DC.AIM II:TO ASCERTAIN THE EFFICACY OF TOLEROGENIC DC IN RHESUS RENAL TRANSPLANTATION AND THEIR IMPACT ON MECHANISMS UNDERLYING IMMUNE REGULATION. Donor and recipient-derived DC will be compared for their ability to prolong renal allograft survival and regulate anti-donor responses in graft recipients. AIM III: TO DETERMINE THE EXTENT TO WHICH CD40-CD154 PATHWAY BLOCKADE AND RAPAMYCIN AUGMENT THE POTENTIAL OF IMMATURE DC TO PROMOTE LONG-TERM, REJECTION-FREE, RENAL ALLOGRAFT SURVIVAL. We will establish the capacity of anti-GDI 54 mAb and the "tolerance-sparing" drug rapamycin to enhance DC tolerogenicity and their potential to promote donor-specific tolerance in the renal transplant model. Excellent facilities and extensive expertise in NHP organ transplantation, post-transplant monitoring (including immunologic monitoring) and experience with relevant therapeutic agents in primates are available to enable and sustain these studies. In clinical transplantation, pre-emptive conditioning of the prospective graft recipient by infusion of in vitro-expanded "tolerogenic" DC (either donor-derived DC or donor allo-Ag-pulsed, recipient DC) is clearly feasible in relation to live donor renal, liver or lung transplantation and may result in donor-specific tolerance.