Reese J S, Koç O N, Gerson S L
Division of Hematology/Oncology, Case Western Reserve University and University Hospitals, Ireland Cancer Center, Cleveland, OH 44106, USA.
J Hematother Stem Cell Res. 1999 Oct;8(5):515-23. doi: 10.1089/152581699319966.
Human mesenchymal stem cells (hMSC)-nonhematopoietic cells within the bone marrow microenvironment that can be culture expanded to a uniform population of fibroblastic cells-have been shown to support long-term hematopoiesis of CD34+ cells. Because direct contact between stromal elements and CD34+ cells enhances long-term engraftment, we postulated that hMSC would be a good alternative to the more heterogeneous stroma currently used in gene transfer studies. We used hMSC to support retroviral gene transfer of the G156A MGMT (deltaMGMT) gene encoding an alkyltransferase (AGT), which confers drug resistance to a combination of O6-benzylguanine (BG) plus the alkylating agents BCNU and temozolomide (TMZ) in human hematopoietic progenitors. In the presence of IL-3, IL-6, SCF, or leukemia inhibitory factor (LIF) and Flt-3 ligand, hMSC facilitated expansion and retroviral transduction of human peripheral blood-mobilized CD34+ cells. Furthermore, the transduced cells expressed AGT in 29% of hematopoietic cells and were 5-fold more resistant to BCNU and TMZ than were untransduced cells. Unirradiated hMSC present as support cells were simultaneously transduced and expressed AGT in 26% of the cells. Thus, the homogeneous nature of hMSC, and their ability to support gene transfer and be transduced themselves suggest they may be useful in clinical gene transfer protocols and have broad therapeutic applications.
人间充质干细胞（hMSC）是骨髓微环境中的非造血细胞，可通过培养扩增为均一的成纤维细胞群体，已被证明能支持CD34+细胞的长期造血。由于基质成分与CD34+细胞之间的直接接触可增强长期植入，我们推测hMSC将是目前基因转移研究中使用的更为异质的基质的良好替代品。我们使用hMSC来支持编码烷基转移酶（AGT）的G156A MGMT（deltaMGMT）基因的逆转录病毒基因转移，该基因可使人造血祖细胞对O6-苄基鸟嘌呤（BG）与烷化剂卡莫司汀（BCNU）和替莫唑胺（TMZ）的联合用药产生耐药性。在白细胞介素-3（IL-3）、白细胞介素-6（IL-6）、干细胞因子（SCF）或白血病抑制因子（LIF）以及Flt-3配体存在的情况下，hMSC促进了人外周血动员的CD34+细胞的扩增和逆转录病毒转导。此外，转导后的细胞在29%的造血细胞中表达AGT，并且对BCNU和TMZ的耐药性比未转导的细胞高5倍。作为支持细胞存在的未照射hMSC同时被转导，并且在26%的细胞中表达AGT。因此，hMSC的同质性及其支持基因转移和自身被转导的能力表明它们可能在临床基因转移方案中有用，并具有广泛的治疗应用。
