Cord Blood Graft Engineering to Improve Engraftment and Reduce GVHD

项目摘要 脐带血移植（CBT）明显优于骨髓移植， 外周血干细胞，但其更广泛的应用受到干细胞低剂量的限制， CB单位中的祖细胞，导致植入延迟和显著的植入率 失败在过去的PO 1资助期间，我们开发了一种骨髓间充质基质细胞， 细胞（MSC）-CB共培养系统，使我们能够显着加快时间的中性粒细胞和 血小板植入。与这一进展并行的是，结果表明离体细胞表面 CB的岩藻糖基化，使用岩藻糖基转移酶（FT）-6酶与GDP-岩藻糖可以促进CB的岩藻糖基化。 通过促进CB向骨髓归巢来促进植入。因此，在项目1中，我们现在提出一个修订的 一系列针对我们长期目标的研究：使CBT的结果与结果一致 G-CSF动员的外周血祖细胞（目的1和2）。这一努力将 基于CB细胞的MSC扩增，然后用以下方法进行外岩藻糖基化的组合测试CBT： FT-7是第二种岩藻糖基转移酶，其比FT-6更具生理性，并且可能比FT-6更具生理性。 有效地增强骨髓中的植入。 此外，移植物抗宿主病（GVHD）继续限制CBT的效用，我们认为这是一个问题。 在过去的PO 1奖项中没有具体说明。CBT后III-IV级GVHD的发生率 从5%到30%不等。在我们的患者中，急性肝脏和胃肠道（GI）GVHD患者 从MSC治疗中获益显著。在异种GVHD模型中，我们观察到， 岩藻糖基化的MSC可以增强归巢到炎症部位，导致惊人的存活率。 与未操作MSC治疗的结果相比，我们最近还 观察到CB组织来源的MSC在逻辑上更容易获得和扩增， 比骨髓来源的MSC更快。因此，我们现在建议测试CB组织来源， 岩藻糖基化MSC可用于消除急性、类固醇难治性肝脏和/或GI GVHD（目的3）。 该项目的互动潜力相当大，例如，目标1中的临床试验将 可能会刺激与项目2（病毒特异性CTL的重建），项目3（NK 细胞恢复）和项目4（肿瘤特异性免疫的恢复）。最后，我们要强调， 项目1的许多发现将不仅限于CBT，而且可能远远超出 移植物抗宿主病和再生医学等多种环境的植入时间。

PROJECT SUMMARY Cord blood transplantation (CBT) has clear advantages over transplantation with bone marrow or peripheral blood stem cells, but its wider use has been limited by the low dose of stem and progenitor cells in CB units, leading to delays in engraftment and a substantial rate of engraftment failure. During the past PO1 funding period, we developed a marrow-derived mesenchymal stromal cell (MSC)-CB coculture system that allowed us to significantly accelerate the time to neutrophil and platelet engraftment. This advance was paralleled by results showing that ex vivo cell-surface fucosylation of CB, using the fucosyltransferase (FT)-6 enzyme with GDP-fucose can boost engraftment by promoting CB homing to marrow. Thus, in Project 1, we now propose a revised series of studies directed to our long-term goal: bringing the results of CBT in line with outcomes being reported for G-CSF-mobilized peripheral blood progenitor cells (Aims 1 and 2). This effort will test CBT based on the combination of MSC-expansion of CB cells followed by exofucosylation with FT-7 a second fucosyltransferase that is more physiologic than FT-6 and could be even more effective at enhancing engraftment in the marrow. Additionally, graft-versus-host disease (GVHD) continues to restrict the utility of CBT, an issue we did not address specifically during the past PO1 award. Rates of grade III-IV GVHD after CBT range from 5% to 30%. In our patients, those with acute liver and gastrointestinal (GI) GVHD have significantly benefited from MSC treatment. In a xenogenic GVHD model, we have observed that fucosylated MSCs can enhance homing to sites of inflammation, resulting in a striking survival benefit compared with the outcome of unmanipulated MSC treatment. We have also recently observed that CB tissue-derived MSCs are logistically easier to obtain and expand much more rapidly than marrow-derived MSCs. Thus we now propose to test whether CB tissue-derived, fucosylated MSCs can be used to abrogate acute, steroid-refractory liver and/or GI GVHD (Aim 3). The interactive potential of this project is considerable, for example, the clinical trial in Aim 1 will likely stimulate collaborations with Project 2 (reconstitution of virus-specific CTLs), Project 3 (NK cell recovery) and Project 4 (recovery of tumor-specific immunity). Finally, we would stress that many of the findings from Project 1 will not be restricted to CBT, but could extend well beyond times to engraftment to settings as diverse as GVHD and regenerative medicine.