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

摘要：总体 对于镰状细胞病(SCD)患者来说，红细胞输注仍然是一种挽救生命的疗法。一位少校 问题是同种异体免疫的高比率(针对输血红细胞的抗体形成)发生在 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赠者池相比，这一高发病率和复杂性 在SCD患者体内发现抗体。寻找相容的红细胞(RBC)单位通常是复杂的 缺乏稀有试剂红细胞来正确识别这些复杂的抗体特异性。这件复杂的事情耽误了 护理，增加了成本，并使一些患者无法接受输血治疗。这样做的最终目的是 建议使用人类诱导多能干细胞(IPSCs)来生产标准和可靠的红血球 细胞(RBC)试剂解决了这一重大问题。我们已经设计了一组基因工程的ipscs 表达血型抗原的独特组合(定制的IPSCs)，这些组合是困难的或虚拟的 在捐献者红细胞中找不到。由这些定制的IPSC生产的RBC试剂将提供 简化和标准化异体免疫患者抗体鉴定的手段，并最终可以 作为未来治疗应用的“通用”供体细胞。我们的努力将解决现有的几个 挑战包括：一、表达血型组合的活体献血者不足或没有 需要抗原来解决SCD，II患者中复杂的抗体特异性。缺少IPSC 分化方案，以产生最终的成人型红细胞，而不使用血清或基质细胞； IPSC衍生的红细胞的制造成本高得令人望而却步。在这份U01申请中，我们建议 来自一组高度协作的调查人员的三个综合项目，他们拥有以下领域的专业知识 应对所有三个挑战，并将通过为当前的这些挑战提供创新解决方案来推动该领域向前发展 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.