Improving transfusion therapy for patients with sickle cell disease with pluripotent stem cell-derived red cells

摘要：总体 红细胞输注仍然是镰状细胞病（SCD）患者的救命疗法。一个主要 问题是发生在体内的同种免疫（针对输注红细胞的抗体形成）的高比率， 输血的SCD患者。非洲裔患者血型抗原的遗传多样性 与主要以欧洲为基础的捐助者库相比， 在SCD患者中发现的抗体。寻找相容的红细胞（RBC）单位通常会因 缺乏稀有试剂RBC来正确鉴定这些复杂的抗体特异性。这种并发症延迟了 护理，增加了成本，并使一些患者无法进行输血治疗。这个项目的最终目标 一项提议是使用人类诱导多能干细胞（iPSC）来生产标准和可靠的红血 红细胞（RBC）试剂来解决这个主要问题。我们设计了一组iPSCs， 表达独特的血型抗原组合（定制的iPSC），这是困难的或几乎 在捐献者的红细胞中找不到。从这些定制的iPSC生产的RBC试剂将提供 意味着简化和标准化同种免疫患者的抗体鉴定，并最终可以 用作未来治疗应用的“通用”供体细胞。我们将努力解决现有的几个问题， 这些挑战包括：表达血型组合的献血者不足或无活血 解决SCD患者中的复杂抗体特异性所需的抗原，ii.缺乏iPSC 分化方案以在不使用血清或基质细胞的情况下产生定型的成人型RBC，和iii. iPSC衍生的RBC的昂贵的制造成本。在U01申请中，我们提出 三个综合项目，来自一组高度合作的研究人员，他们在以下领域拥有专业知识： 解决所有这三个挑战，并将通过提供创新的解决方案，以推动该领域的发展，这些目前 障碍.

ABSTRACT: OVERALL Red blood cell transfusion remains a life-saving therapy for patients with sickle cell disease (SCD). A major problem is the high rate of alloimmunization (antibody formation against transfused red cells) that occurs in transfused patients with SCD. Genetic diversity in blood group antigens in patients of African descent compared to the primarily European-based donor pool contributes to this high incidence and complexity of antibodies found in patients with SCD. Finding compatible red blood cell (RBC) units is often complicated by a lack of rare reagent RBCs to properly identify these complex antibody specificities. This complication delays care, increases costs, and makes transfusion therapy impossible for some patients. The ultimate goal of this proposal is to use human induced pluripotent stem cells (iPSCs) to produce standard and reliable red blood cell (RBC) reagents to resolve this major problem. We have designed a panel of iPSCs genetically engineered to express unique combinations of blood group antigens (customized iPSCs) that are difficult or virtually impossible to find in donor RBCs. RBC reagents produced from these customized iPSCs will provide the means to streamline and standardize antibody identification in alloimmunized patients, and ultimately can be used as “universal” donor cells for future therapeutic applications. Our efforts will address several existing challenges that include: i. insufficient or no living blood donors expressing the combinations of blood group antigens needed to resolve the complex antibody specificities in patients with SCD, ii. lack of iPSC differentiation protocols to produce definitive, adult-type RBCs without the use of serum or stromal cells, and iii. the prohibitively expensive manufacturing costs of iPSC-derived RBCs. In this U01 application, we propose three integrated Projects from a group of highly collaborative investigators with expertise in areas that can address all three challenges and will drive the field forward by providing innovative solutions to these current obstacles.