基因治疗课程-梁旻2.ppt

血友病 1:5000 男性发病 80% A 型血友病缺乏 VIII 因子 20% B 型血友病缺乏 IX 因子 造成自发性流血，可以致命。 输入缺乏的因子可以起到预防和治疗的作用 重建 1% 的基因活性可以减少自发性流血 重建 10% 的基因活性可以治愈自发性流血 血友病的基因治疗方法 经肝介导 经肌肉介导 经骨髓介导 移植经基因修饰的成纤维细胞 体外/体内vs.体内经肝介导方法 Ex Vivo: Remove hepatocytes Modify in culture Reinject In Vivo: Inject vector 经肝介导的不同载体 AAV (Adenovirus associated virus) Vectors Good expression for hemophilia B Safe Retroviral vectors Good expression for hemophilia A and B Safe Adenoviral vectors Great expression for hemophilia A or B No stable efficacy in large animals 腺相关病毒 (AAV) 载体 Small single-stranded DNA (4.5 kb) virus of the parvovirus family Does not require replicating cells for gene transfer Effect of AAV-mediated Hepatic Gene Therapy in Hemophilia B Dogs 逆转录病毒载体 Single stranded RNA virus that gets copied into DNA that integrates into the chromosome Classes of retroviral vectors: Oncoretroviral vectors require replication for gene transfer Lentiviral vectors do not require replication for gene transfer Ways for Oncoretroviral Vectors to Transduce Hepatocytes: Adults: Inject hepatocyte growth factor (HGF) prior to injection of retroviral vectors Newborns: Replication is already sufficient for gene transfer due to the rapid rate of growth Oncoretroviral vector Transfer into Adult Mice Oncoretroviral Vector Transfer of Canine FIX into Neonatal Mice: 给新生小狗注射 Oncoretroviral Vector Transfer into Newborn Hemophilia B Dogs 对B型血友病新生狗基因治疗结果 Achieved 10% to 35% of normal antigen; about 30% was functional There was a reduction in bleeding in one dog No antibody responses occurred 人体临床试验 IM injection of AAV for hemophilia B IV injection of RV for hemophilia A Implantation of genetically-modified fibroblasts for hemophilia A Hepatic artery injection of AAV for hemophilia B 肌肉注射AAV载体 静脉注射逆转录病毒载体治疗A型血友病 Based on inconsistent results in animals, in which some animals with high antibody levels had high antigen levels, but no coagulation activity Injected RV IV without a stimulus for hepatocyte