Kirschner Andreas, Thiede Melanie, Grünewald Thomas G P, Alba Rubio Rebeca, Richter Günther H S, Kirchner Thomas, Busch Dirk H, Burdach Stefan, Thiel Uwe
Laboratory for Functional Genomics and Transplantation Biology, Department of Pediatrics and Children's Cancer Research Center, Klinikum rechts der Isar, Technische Universität München , München, Germany.
Max-Eder Research Group for Pediatric Sarcoma Biology, Institute of Pathology of the LMU Munich, München, Germany; German Cancer Consortium (DKTK), Heidelberg, Germany; German Cancer Research Center (DKFZ), Heidelberg, Germany.
Oncoimmunology. 2017 Jan 17;6(2):e1273301. doi: 10.1080/2162402X.2016.1273301. eCollection 2017.
Pregnancy-associated plasma protein-A (PAPPA), also known as pappalysin, is a member of the insulin-like growth factor (IGF) family. PAPPA acts as a protease, cleaving IGF inhibitors, i.e., IGF binding proteins (IGFBPs), thereby setting free IGFs. The insulin/IGF-axis is involved in cancer in general and in Ewing sarcoma (ES) in particular. ES is a highly malignant bone tumor characterized by early metastatic spread. PAPPA is associated with various cancers. It is overexpressed and required for proliferation in ES. PAPPA also stimulates normal bone growth. We isolated HLA-A02:01/peptide-restricted T cells from A02:01 healthy donors directed against PAPPA, generated by priming with A02:01 PAPPA peptide loaded dendritic cells. After TCR identification, retrovirally TCR transduced CD8 T cells were assessed for their specificity and efficacy in human ES bearing Rag2γc mice. Engraftment in mice and tumor infiltration of TCR transgenic T cells in the mice was evaluated. The TCR transgenic T cell clone PAPPA-2G6 demonstrated specific reactivity toward HLA-A02:01/PAPPA ES cell lines. We furthermore detected circulating TCR transgenic T cells in the blood in Rag2γc mice and engraftment in bone marrow. Tumor growth in mice with xenografted ES was significantly reduced after treatment with PAPPA-2G6 TCR transgenic T cells in contrast to controls. Tumors of treated mice revealed tumor-infiltrating PAPPA-2G6 TCR transgenic T cells. In summary, we demonstrate that PAPPA is a first-rate target for TCR-based immunotherapy of ES.
妊娠相关血浆蛋白-A（PAPPA），也称为妊娠相关血浆蛋白裂解素，是胰岛素样生长因子（IGF）家族的成员。PAPPA作为一种蛋白酶，裂解IGF抑制剂，即IGF结合蛋白（IGFBPs），从而释放出IGF。胰岛素/IGF轴一般参与癌症，尤其是尤因肉瘤（ES）。ES是一种高度恶性的骨肿瘤，其特征是早期转移扩散。PAPPA与多种癌症相关。它在ES中过度表达且是增殖所必需的。PAPPA还刺激正常骨生长。我们从A02:01健康供体中分离出针对PAPPA的HLA-A02:01/肽限制性T细胞，这些T细胞是通过用负载A02:01 PAPPA肽的树突状细胞进行致敏产生的。在TCR鉴定后，对逆转录病毒TCR转导的CD8 T细胞在携带Rag2γc基因敲除小鼠的人ES中的特异性和功效进行了评估。评估了TCR转基因T细胞在小鼠中的植入情况以及在小鼠肿瘤中的浸润情况。TCR转基因T细胞克隆PAPPA-2G6对HLA-A02:01/PAPPA ES细胞系表现出特异性反应。我们还在Rag2γc基因敲除小鼠的血液中检测到循环的TCR转基因T细胞以及在骨髓中的植入情况。与对照组相比，用PAPPA-2G6 TCR转基因T细胞治疗后，异种移植ES小鼠的肿瘤生长显著减少。治疗小鼠的肿瘤显示有肿瘤浸润的PAPPA-2G6 TCR转基因T细胞。总之，我们证明PAPPA是ES基于TCR免疫治疗的一流靶点。
