Gerull Sabine, Beard Brian C, Peterson Laura J, Neff Tobias, Kiem Hans-Peter
Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.
Hum Gene Ther. 2007 May;18(5):451-6. doi: 10.1089/hum.2006.039.
We have previously demonstrated successful in vivo selection, chemoprotection, and modulation of donor chimerism in dogs that received myeloablative allogeneic stem cell transplantation with cells expressing the P140K mutant of the DNA repair enzyme methylguanine methyltransferase (MGMTP140K). Here, we wished to investigate whether in vivo selection, chemoprotection, and modulation of donor chimerism could also be achieved after nonmyeloablative transplantation, which could allow for less toxic transplantation regimens for patients with malignant and genetic diseases. Three dogs received a nonmyeloablative conditioning regimen and infusion of allogeneic stem cells transduced with MGMTP140K. All three dogs had stable gene marking and donor chimerism before receiving a course of O(6) -benzylguanine (O(6) BG)/1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) between days 210 and 589 after transplantation. One to four doses led to a marked increase in gene marking in all dogs. Furthermore, the transduced cells conferred chemoprotection and prevented severe neutropenia. Our results suggest that drug resistance gene therapy is feasible and safe in the nonmyeloablative transplantation setting.
我们之前已证明，在接受了清髓性异基因干细胞移植的犬类中，使用表达DNA修复酶甲基鸟嘌呤甲基转移酶（MGMTP140K）P140K突变体的细胞进行体内选择、化学保护和调节供体嵌合率是成功的。在此，我们希望研究在非清髓性移植后是否也能实现体内选择、化学保护和调节供体嵌合率，这可能为患有恶性和遗传性疾病的患者提供毒性较小的移植方案。三只犬接受了非清髓性预处理方案并输注了用MGMTP140K转导的异基因干细胞。在移植后第210天至589天接受一个疗程的O(6)-苄基鸟嘌呤（O(6)BG）/1,3-双（2-氯乙基）-1-亚硝基脲（BCNU）之前，所有三只犬都有稳定的基因标记和供体嵌合率。一至四剂导致所有犬的基因标记显著增加。此外，转导的细胞提供了化学保护并预防了严重的中性粒细胞减少。我们的结果表明，耐药基因治疗在非清髓性移植环境中是可行且安全的。
