以前,我们报道了人类Aγ-珠蛋白基因慢病毒(LV)的发展,GBG,在伯克利SCA小鼠模型中表达高水平的HbF以纠正镰状细胞性贫血(SCA)表型,然后通过用Aγ-珠蛋白基因中的天冬氨酸取代密码子16处的甘氨酸来修饰γ-珠蛋白基因,以生成GbGMLV。在本研究中,我们评估了携带GbGMLV的人Aγ-珠蛋白基因在野生型小鼠初次和二次移植GbGM修饰的造血干细胞(HSC)18个月后的长期安全性.通过监测对体重的影响来评估GbGM骨髓移植的安全性,血液学,组织病理学,恶性肿瘤形成,和生存。用模拟转导和脾病灶形成病毒(SFFV)γ-逆转录病毒载体(RV)转导的HSC移植的小鼠作为阴性和阳性对照,分别。平均供体细胞移植与模拟细胞相当,GBGMLV,和SFFVRV组。体重没有显着差异,临床体征,免疫表型,或与对照组相比,GbGM处理的小鼠的组织病理学。四只SFFVRV治疗的小鼠,但是GbGM治疗的小鼠中没有一个,发达的捐赠者来源,通过流式细胞术分析和原位杂交证明的载体阳性淋巴瘤。这些结果强调了在小鼠初次和二次移植后长期随访中施用GbGMLV修饰的HSC的安全性。该数据支持在美国启动1/2期首次人SCA临床试验。
Previously, we reported the development of a human Aγ-globin gene lentivirus (LV), GbG, which expresses high levels of HbF to correct the sickle cell anemia (SCA) phenotype in the Berkeley SCA mouse model, and then modified the γ-globin gene by substituting glycine at codon 16 with aspartic acid in the Aγ-globin gene to generate GbGM LV. In the present study, we evaluated the long-term safety of human Aγ-globin gene carrying GbGM LV in wild-type mice after primary and secondary transplants of GbGM-modified hematopoietic stem cells (HSC) over 18 months. The safety of the GbGM bone marrow transplant was assessed by monitoring the effects on body weight, hematology, histopathology, malignancy formation, and survival. Mice transplanted with Mock-transduced and spleen focus forming virus (SFFV) γ-retroviral vector (RV)-transduced HSC served as negative and positive controls, respectively. The mean donor-cell engraftment was comparable across Mock, GbGM LV, and SFFV RV groups. There were no significant differences in body weight, clinical signs, immunophenotype, or histopathology in the GbGM-treated mice compared to controls. Four SFFV RV-treated mice, but none of the GbGM-treated mice, developed donor-derived, vector-positive lymphomas as demonstrated by flow cytometry analysis and in situ hybridization. These results highlight the safety of the administration of GbGM LV-modified HSC with long-term follow-up after primary and secondary transplants in mice. This data supported the initiation of phase 1/2 first-in-human SCA clinical trial in the United States.