Chang P L, Shen N, Westcott A J
Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
Hum Gene Ther. 1993 Aug;4(4):433-40. doi: 10.1089/hum.1993.4.4-433.
If established cultured cell lines genetically modified to secrete desired gene products could be implanted in different allogeneic recipients without immune rejection, novel gene products would be delivered more cost effectively. We tested this strategy by encapsulating mouse Ltk- cells transfected with the human growth hormone (hGH) gene in immunoprotective perm-selective alginate microcapsules. Allogeneic mice implanted with these microcapsules demonstrated hGH in their circulation (0.1-1.5 ng/ml serum) within the first 2 weeks. Control mice implanted with only the transfected cells without microcapsules did not demonstrate significant levels of circulating hGH. By about 3 weeks, antibodies against hGH developed in the microcapsule-implanted mice. The immune response was detected only against the hGH and no other secretory products from the transfected cells. The antibody titer continued to escalate for more than three months, thus demonstrating indirectly the continued delivery of the growth hormone. The persistent expression of the transgene and survival of the transfected cells were verified when the microcapsules were retrieved periodically to demonstrate that the encapsulated cells remained viable, proliferative, and productive of hGH even by 78-111 days. In conclusion, delivering gene products with genetically modified allogeneic cells in vivo has been shown feasible for prolonged periods. This technology should have potential applications in somatic gene therapy and in treatment of other somatic diseases.
如果经过基因改造以分泌所需基因产物的已建立培养细胞系能够植入不同的异基因受体而不发生免疫排斥，那么新型基因产物的递送将更具成本效益。我们通过将转染了人生长激素（hGH）基因的小鼠Ltk-细胞封装在免疫保护的选择性渗透海藻酸盐微胶囊中来测试这一策略。植入这些微胶囊的异基因小鼠在最初2周内其循环系统中出现了hGH（血清中0.1 - 1.5 ng/ml）。仅植入未封装转染细胞的对照小鼠未检测到显著水平的循环hGH。到大约3周时，植入微胶囊的小鼠体内产生了抗hGH抗体。仅检测到针对hGH的免疫反应，未检测到转染细胞的其他分泌产物。抗体滴度持续上升超过三个月，从而间接证明了生长激素的持续递送。当定期取出微胶囊以证明即使到78 - 111天时，封装的细胞仍保持存活、增殖并产生hGH时，验证了转基因的持续表达和转染细胞的存活。总之，在体内用基因改造的异基因细胞递送基因产物已被证明在长时间内是可行的。这项技术在体细胞基因治疗和其他体细胞疾病的治疗中应具有潜在应用。
