人骨髓间充质干细胞表达多种造血细胞因子

为了研究培养的人骨髓间充质干细胞在造血中的生物作用，采用RT—PCR方法在mRNA水平上分析体外培养的人骨髓间充质干细胞(BM—MSC)造血因子的表达，以及氢化考的松对BM—MSC表达造血细胞因子的影响。结果显示，体外传代培养的正常人、白血病和淋巴瘤等血液病人BM—MSC均能表达SCF，Flt3-ligand TPO,LIF,IL—6和IL—11等重要的造血细胞因子，但不表达G—CSF，GM—CSF和IL-3。不同代数的BM—MSC细胞，造血细胞因子的表达相同。BM—MSC经氢化考的松作用7—21天后，可谤手G—GSFmRNA表达，但不诱导GM—GSF的表达，细胞在形态学上也未发生明显改变。结论：体外培养的正常人和本组血液病病人BM—MSC具有促造血功能。     

Immortalized multipotential mesenchymal cells and the hematopoietic microenvironment

In an attempt to analyze the cellular and molecular basis of the capacity of bone marrow stromal cells to support hematopoiesis in culture, we developed a series of murine stromal cell lines from a single long-term bone marrow culture (BMC). The cytokines produced by these cells were analyzed using immunohistochemical techniques, ribonuclease protection assays (RPA) and RT-PCR. We examined the capacity of these cloned cell lines to replace primary bone marrow-derived stromal cells in long-term bone marrow cultures (LT-BMC) and sought correlations between the capacity to support hematopoiesis in culture with the production of known cytokines. These immortalized lines replicate many of the functions of the hematopoietic microenvironment. They express cytokines known to play a role in hematopoiesis. All of the lines constitutively express mRNA for PBSF (SDF-1), macrophage colony-stimulating factor (M-CSF), stem cell factor (SCF), FLT-3, thrombopoietin (TPO), interleukin 7 (IL-7), leukemia inhibitory factor (LIF), tumor necrosis factor-beta (TNF-beta), and interferon-gamma (IFN-gamma). Most lines also express granulocyte-macrophage colony-stimulating factor (GM-CSF) and G-CSF. They vary in their expression of IL-6, tumor growth factor-beta1 (TGF-beta1), TGF-beta2, and TNF-alpha. Growing these lines in the presence of cytokines that influence hematopoiesis alters the levels of cytokine message. The most striking effects were produced by TNF-alpha. In addition to the cytokine mRNAs, the cell lines express factors associated with bone formation such as osteoblast-specific factor-2 (OSF-2) and bone morphogenetic protein-1 (BMP-1). They also express the neural cell-adhesion molecule neuropilin and neurotrophic factors including nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF). Several of the lines can maintain hematopoiesis in culture, as measured by the continuous production of myeloid colony-forming cells (CFU-c), for months. This capacity to support hematopoiesis does not correlate with any pattern of cytokine expression. Several of these lines also support the growth of human hematopoietic cells, and human CFU-c can be detected in the cultures in which CD34(+) bone marrow cells (BMC) are cultured on murine stromal cells. No correlation between the production of any of the known cytokines and the ability to support murine hematopoiesis was detected. In addition, there was no correlation between the capacity to support murine hematopoiesis and the capacity to maintain human HSC. Despite repeated cloning, the lines remain heterogeneous and are capable of producing cells with the properties of fibroblasts, osteoblasts, adipocytes, and myoblasts. In addition to the cytokine mRNAs, the cell lines express factors associated with bone formation such as OSF-2 and BMP-1. They also express the neural cell-adhesion molecule neuropilin and neurotrophic factors including NGF and BDNF.     

Premature expression of the macrophage colony-stimulating factor receptor on a multipotential stem cell line does not alter differentiation lineages controlled by stromal cells used for coculture

We are interested to know whether expression of a lineage-specific growth factor receptor is deterministic to lineage commitment during hematopoiesis. For this purpose, we introduced the human c-fms gene into the multipotential stem cell clone LyD9 and two myeloid progenitor clones, L-GM3 and L-G3, cells that differentiate in response to granulocyte/macrophage colony-stimulating factor (GM-CSF) and granulocyte (G)-CSF, respectively. Although LyD9 cells have differentiation potential to become macrophages, c-fms transfectants of LyD9 and L-GM3 cells did not differentiate in response to human macrophage (M)-CSF. However, c-fms transfectants of L-G3 cells differentiated to neutrophils in response to human M-CSF. These results indicate that the M-CSF receptor requires a specific signal transduction pathway to exert its differentiational and proliferative effects. Furthermore, the M-CSF receptor can convey a granulocyte-type differentiation signal possibly by cooperating with the G-CSF receptor signal transduction pathway. The c-fms-transfected LyD9 cells as well as the original LyD9 cells differentiated predominantly into GM-CSF- and G-CSF-responsive cells by coculturing with PA6 and ST2 stromal cells, respectively. The results indicate that differentiation lineage is not affected by premature expression of the M-CSF receptor. Instead, the stromal cell used for coculture apparently controls lineage-selective differentiation of the multi-potential stem cell line.     

Rhodamine123 reveals heterogeneity within murine Lin-, Sca-1+ hemopoietic stem cells

Murine bone marrow Lin-, Ly6A/E+ cells have been fractionated on the basis of rhodamine123 retention into Rh123med/hi and Rh123lo subpopulations. These populations have different responses to hemopoietic growth factors with respect to in vitro colony formation. Cells from either fraction were not stimulated by only granulocyte-colony-stimulating factor (G-CSF), granulocyte/macrophage colony-stimulating factor (GM-CSF), macrophage colony-stimulating factor (M-CSF), interleukins 1 and 6 (IL-1 and -6), or leukemia inhibitory factor (LIF) alone. The Rh123med/hi, but not the Rh123lo fraction, contained cells that could be stimulated by either stem cell factor (SCF) or IL-3 alone. When combinations of growth factors were added, the Rh123med/hi fraction produced more colonies, and responded to a wider range of factor combinations than the Rh123lo population. When tested in vivo, both populations contained no detectable day 8 colony-forming unit-spleen (CFU-S), and similar frequencies of day 13 CFU-S. When transplanted into lethally irradiated recipients (100 cells/recipient), significant numbers of donor cells (67-73%) were found in the peripheral blood of Rh123lo recipients. Both myeloid and lymphoid cells were of donor origin. By comparison, the Rh123med/hi population produced recipients with 1-2% donor cells in peripheral blood, the majority of which were lymphoid.     

Messenger RNA expression of the cytokine gene cluster, interleukin 3 (IL-3), IL-4, IL-5, and granulocyte/macrophage colony-stimulating factor, in allergen-induced late-phase cutaneous reactions in atopic subjects

Cryostat sections from skin biopsies from 24-h allergen-induced late-phase cutaneous reactions (LPR) in 14 human atopic subjects were hybridized with 35S-labeled RNA probes for a number of cytokines. mRNA was detected for interleukin 3 (IL-3) (8/14), IL-4 (10/14), IL-5 (11/14), and granulocyte/macrophage colony-stimulating factor (GM-CSF) (13/14). Only 5 of 14 gave hybridization signals for IL-2, and 0 of 14 for interferon gamma. Biopsies from diluent controls gave only occasional weak signals. These results suggest that cells infiltrating the site of the 24-h LPR transcribe mRNA for the IL-3, IL-4, IL-5, and GM-CSF gene cluster and support the hypothesis that atopy is associated with preferential activation of cells having a similar cytokine profile to the murine T helper type 2 subset.     

Growth factor-dependent inhibition of normal hematopoiesis by N-ras antisense oligodeoxynucleotides

To determine whether N-ras expression is required at specific stages of the process of in vitro normal human hematopoiesis, adherent- and T lymphocyte-depleted mononuclear marrow cells (A-T-MNC) or highly purified progenitors (CD34+ cells) were cultured in semisolid medium, under conditions that favor the growth of specific progenitor cell types, after exposure to N-ras sense and antisense oligodeoxynucleotides. N-ras antisense, but not sense, oligodeoxynucleotide treatment of A-T-MNC and CD34+ cells resulted in a significantly decreased number of granulocyte/macrophage colony-forming units (CFU-GM) induced by interleukin 3 (IL-3) or granulocyte/macrophage colony-stimulating factor (GM-CSF) and of macrophage colonies (CFU-M) induced by M-CSF, but not of granulocytic colonies induced with G-CSF or IL-5. However, the same treatment significantly inhibited colony formation induced by each of the above factors in combination with IL-3. Megakaryocytic colony (CFU-Meg) formation from A-T-MNC or CD34+ cells in the presence of IL-6 + IL-3 + erythropoietin (Epo) was also markedly decreased after antisense oligodeoxynucleotide treatment. Erythroid colonies derived from A-T-MNC in the presence of Epo (CFU-E) were not inhibited upon antisense treatment, whereas those arising from A-T-MNC or CD34+ cells in the presence of IL-3 + Epo (BFU-E) were markedly affected. These results are consistent with the hypothesis that distinct signal transduction pathways, involving N-ras or not, are activated by different growth factors in different hematopoietic progenitor cells.     

Cytokines in chronic inflammatory arthritis. V. Mutual antagonism between interferon-gamma and tumor necrosis factor-alpha on HLA-DR expression, proliferation, collagenase production, and granulocyte macrophage colony-stimulating factor production by rheumatoid arthritis synoviocytes

The effects of a broad array of cytokines, individually and in combination, were determined on separate functions (proliferation, collagenase production, and granulocyte macrophage colony-stimulating factor [GM-CSF] production) and phenotype (expression of class II MHC antigens) of cultured fibroblast-like RA synoviocytes. The following recombinant cytokines were used: IL-1 beta, IL-2, IL-3, IL-4, IFN-gamma, tumor necrosis factor (TNF)-alpha, GM-CSF, and macrophage colony-stimulating factor (M-CSF). Only IFN-gamma induced HLA-DR (but not HLA-DQ) expression. TNF-alpha inhibited IFN-gamma-mediated HLA-DR expression (46.7 +/- 4.1% inhibition) and HLA-DR mRNA accumulation. This inhibitory effect was also observed in osteoarthritis synoviocytes. Only TNF-alpha and IL-1 increased synoviocyte proliferation (stimulation index 3.60 +/- 1.03 and 2.31 +/- 0.46, respectively). IFN-gamma (but none of the other cytokines) inhibited TNF-alpha-induced proliferation (70 +/- 14% inhibition) without affecting the activity of IL-1. Only IL-1 beta and TNF-alpha induced collagenase production (from less than 0.10 U/ml to 1.10 +/- 0.15 and 0.72 +/- 0.24, respectively). IFN-gamma decreased TNF-alpha-mediated collagenase production (69 +/- 19% inhibition) and GM-CSF production but had no effect on the action of IL-1. These data demonstrate mutual antagonism between IFN-gamma and TNF-alpha on fibroblast-like synoviocytes and suggest a novel homeostatic control mechanism that might be defective in RA where very little IFN-gamma is produced.     

体外培养的人AGM区基质细胞表达多种造血生长因子

本研究检测人胚胎主动脉-性腺-中肾（AGM）区基质细胞表达的造血生长因子，为探讨AGM区基质细胞在胚胎造血发生中的作用及其造血支持作用提供基础资料。采用RT—PCR方法在mRNA水平分析IL-6、SCF、Fit3-L、OSM、IL-3、TPO、M-CSF、LIF等因子在人AGM区基质细胞（hAGMSI—S5）的表达情况，应用ELISA法测定IL-6、SCF、Fit3-L在hAGMSI—S5细胞培养上清液中的分泌水平，并将脐血CD34^＋细胞与hAGMSI—S5饲养层细胞共培养14天后行造血细胞集落培养以进一步检测人AGM区基质细胞的造血支持作用。结果表明：hAGMSI—S5均表达IL-6、SCF、Flt3-L、OSM等造血生长因子mRNA，不表达IL-3、TPO、M-CSF、LIF等因子mRNA。在hAGMSI—S5细胞培养上清液中可测得分泌的SCF、Fit3-L、IL-6等因子，hAGMSI—S5组间比较各因子水平无显著性差异（P〉0．05）。集落培养结果表明，hAGMSI—S5对CFU—GM、BFU—E、CFU-Mix均有不同程度的扩增作用，hAGMSI—S5的造血支持作用组间比较亦显示有显著性差异（P〈0.05），其中hAGMS3,S4优于S1、S2及S5。结论：人AGM区基质细胞表达SCF、Fit3-L、IL-6、OSM等多种造血生长因子，这可能与AGM区基质细胞支持造血细胞原始发生和体外维持造血干细胞功能相关。     

间充质干细胞与相关因子

间充质干细胞(mesenchymal stem cell，MSC)具有向成骨细胞、成软骨细胞、脂肪细胞及成肌细胞分化的多向潜能，可在造血微环境形成、组织修复及基因治疗中得到应用。多种生长因子如TGF—β，IGF—I，BMP及FGF在MSC分化中发挥不同的促进作用并有协同性；MSC可分泌G—CSF，SCF，LIF，M—CSF，IL—6和IL—11等多种细胞因子支持造血并与某些疾病的发生有关；相关因子作用后的MSC将在基因工程应用中发挥重要作用。     

干细胞生长因子和粒细胞集落刺激因子与心肌梗死大鼠体内骨髓间充质干细胞的迁移

背景:外周静脉移植间充质干细胞只有1%～5%的移植细胞能归巢到心肌梗死区域。目的:观察干细胞生长因子、粒细胞集落刺激因子对骨髓间充质干细胞归巢的影响。方法:采用贴壁培养法分离培养SD大鼠骨髓间充质干细胞,取传至3～5代细胞。建立SD大鼠急性心肌梗死模型,干细胞生长因子组、粒细胞集落刺激因子组、干细胞生长因子+粒细胞集落刺激因子组在骨髓间充质干细胞移植前3d和移植后3d单独或混合皮下注射干细胞生长因子、粒细胞集落刺激因子,骨髓间充质干细胞组不注射细胞因子。结果与结论:荧光显微镜下观察,骨髓间充质干细胞迁移至心肌梗死组织,骨髓间充质干细胞组、干细胞生长因子组、粒细胞集落刺激因子组迁移至心肌梗死区的骨髓间充质干细胞数量没有明显的区别(P>0.05),干细胞生长因子+粒细胞集落刺激因子组的骨髓间充质干细胞数量明显高于其他3组(P<0.05)。免疫荧光组织化学显示,植入的部分骨髓间充质干细胞表达心肌特异蛋白cTnI。结果说明干细胞生长因子和粒细胞集落刺激因子两种细胞因子联合应用可以促进骨髓间充质干细胞归巢至心肌梗死区域,在体内微环境的诱导下,骨髓间充质干细胞能够转化为心肌样细胞。     

Cytokines and macrophages

Macrophages, within the cytokine network, are a major source of many cytokines involved in immune response, hematopoiesis, inflammation and many other homeostatic processes. Upon stimulation by micro-organisms, microbial products or endogenous factors including cytokines, macrophages can de novo synthesize and release a large variety of cytokines (ie IL-1, IL-Ira, IL-6, IL-8, IL-10, IL-12, TNFα, IFNα, IFNy, MCP-l, MCP-3, MIF, M-CSF, G-CSF, GM-CSF, MIP-l, MIP-2, LIF, OSM, TGFβ). Some cytokines can upregulate the production of cytokines by macrophages (IL-3, GM-CSF, IFNγ) while others can inhibit it (IL-4, IL-10, IL-13, TGFβ). In addition, these cytokines can modulate most of the macrophage functions and cell surface marker expression. Other cytokines (the chemokines such as MCP-1,2,3, MIP-1,2 and RANTES) contribute to the recruitment of circulating monocytes within tissues. It is worth noting that macrophages can be their own source of regulatory cytokines.     

CD40 expression by human monocytes: regulation by cytokines and activation of monocytes by the ligand for CD40

CD40 is a member of the tumor necrosis factor (TNF) receptor family of cell surface proteins and was originally described as a B cell restricted antigen. Treatment of primary human monocytes with granulocyte/macrophage colony-stimulating factor (GM-CSF), interleukin 3 (IL-3), or interferon gamma (IFN-gamma) resulted in the induction of CD40 mRNA and enhancement of cell surface protein expression. CD40 was found to mediate monocyte adhesion to cells expressing recombinant CD40 ligand. CD40 ligand-transfected cells provided a potent costimulus for monocyte TNF-alpha and IL-6 production in the presence of GM-CSF, IL-3, or IFN-gamma, and enhanced IL-8 production stimulated by GM-CSF or IL- 3. In addition, CD40 ligand-transfected cells acting in the absence of a costimulus induced monocytes to become tumoricidal against a human melanoma cell target. Collectively, these data indicate that CD40 ligand is pleiotropic with potent biological activity on monocytes.     

Regulation of parasite-induced eosinophilia: selectively increased interleukin 5 production in helminth-infected patients

Production of the eosinophilogenic cytokines interleukin 3 (IL-3), granulocyte/macrophage colony-stimulating factor (GM-CSF), and IL-5 by mitogen-stimulated peripheral blood mononuclear cells was compared between 11 noneosinophilic individuals and seven patients with helminth-induced eosinophilia. Both the kinetics and quantities of IL-3 and GM-CSF were similar in the two groups. In contrast, IL-5 production at both the protein and the mRNA level was markedly greater in the eosinophilic patients, an observation suggesting that IL-5 may be particularly important in mediating the selective eosinophilia seen in filarial and other helminth infections.     

Hematopoietic growth factors in clinical hematology.

Five primary hematopoietic growth factors have been extensively evaluated in trials in patients with inadequate blood cell formation. Results have convincingly demonstrated that various chronic anemias can be corrected with erythropoietin. Similarly, there is no doubt that granulocyte-macrophage colony-stimulating factor (GM-CSF) and granulocyte colony stimulating factor (G-CSF) increase the number of leukocytes and improve the function of cells in patients with congenital and acquired leukopenias. Recent studies indicate that interleukin-3 (IL-3) and macrophage colony-stimulating factor (M-CSF) can also stimulate blood cell production in patients. As a result, morbidity and perhaps mortality associated with severe cytopenias can be reduced substantially.     

Cytokine-dependent long-term culture of highly enriched precursors of hematopoietic progenitor cells from human bone marrow.

Human marrow cells positive for the CD34 antigen but not expressing HLA-DR, CD15, or CD71 antigens were isolated. In a liquid culture system supplemented with 48-hourly additions of recombinant interleukins IL-1 alpha, IL-3, IL-6, or granulocyte/macrophage colony-stimulating factor (GM-CSF), these cells were capable of sustaining in vitro hematopoiesis for up to eight weeks. The establishment of an adherent cell layer was never observed. Cultures containing no exogenous cytokine produced clonogenic cells for only 1 wk. IL-1 alpha and IL-6 were alone able to support hematopoiesis for 2 or 3 wk. Cells maintained with GM-CSF proliferated and contained assayable colony-forming cells for 3 or 4 wk, while maximal cellular expansion and generation of assayable progenitor cells occurred in the presence of IL-3 for 4-5 wk. When IL-3 was combined with IL-1 alpha or IL-6, hematopoiesis was sustained for 8 wks. Basophil numbers were markedly increased in the presence of IL-3. These studies indicate that marrow subpopulations can sustain hematopoiesis in vitro in the presence of repeated additions of cytokines. We conclude that a major function of marrow adherent cells in long-term cultures is that of providing cytokines which promote the proliferation and differentiation of primitive hematopoietic cells.     

Transforming growth factor beta 1 selectively regulates early murine hematopoietic progenitors and inhibits the growth of IL-3-dependent myeloid leukemia cell lines

Transforming growth factor beta 1 (TGF-beta 1) has been shown to be associated with active centers of hematopoiesis and lymphopoiesis in the developing fetus. Therefore, the effects of TGF-beta 1 on mouse hematopoiesis were studied. TGF-beta 1 is a potent inhibitor of IL-3-induced bone marrow proliferation, but it does not inhibit the proliferation induced by granulocyte/macrophage, colony-stimulating factor (CSF), granulocyte CSF, and erythropoietin (Epo). TGF-beta 1 also inhibits IL-3-induced multipotential colony formation of bone marrow cells in soft agar, which includes early erythroid differentiation, while Epo-induced terminal differentiation is unaffected. In addition, IL-3-induced granulocyte/macrophage colonies were inhibited; however, small clusters of differentiated myeloid cells were consistently seen in cultures containing IL-3 and TGF-beta 1. Thus, TGF-beta 1 selectively inhibits early hematopoietic progenitor growth and differentiation but not more mature progenitors. TGF-beta 1 is also a potent inhibitor of IL-3-dependent and -independent myelomonocytic leukemic cell growth, while the more mature erythroid and macrophage leukemias are insensitive. Therefore, TGF-beta 1 functions as a selective regulator of differentiating normal hematopoietic cells, and suppresses myeloid leukemic cell growth.     

Tumor necrosis factor-alpha inhibits stem cell factor-induced proliferation of human bone marrow progenitor cells in vitro. Role of p55 and p75 tumor necrosis factor receptors.

Stem cell factor (SCF), a key regulator of hematopoiesis, potently synergizes with a number of hematopoietic growth factors. However, little is known about growth factors capable of inhibiting the actions of SCF. TNF-alpha has been shown to act as a bidirectional regulator of myeloid cell proliferation and differentiation. This study was designed to examine interactions between TNF-alpha and SCF. Here, we demonstrate that TNF-alpha potently and directly inhibits SCF-stimulated proliferation of CD34+ hematopoietic progenitor cells. Furthermore, TNF-alpha blocked all colony formation stimulated by SCF in combination with granulocyte colony-stimulating factor (CSF) or CSF-1. The synergistic effect of SCF observed in combination with GM-CSF or IL-3 was also inhibited by TNF-alpha, resulting in colony numbers similar to those obtained in the absence of SCF. These effects of TNF-alpha were mediated through the p55 TNF receptor, whereas little or no inhibition was signaled through the p75 TNF receptor. Finally, TNF-alpha downregulated c-kit cell-surface expression on CD34+ bone marrow cells, and this was predominantly a p55 TNF receptor-mediated event as well.     

Interleukin 10 inhibits growth and granulocyte/macrophage colony- stimulating factor production in chronic myelomonocytic leukemia cells

Autonomous release of hematopoietic growth factors may play a crucial role in the pathogenesis of certain hematological malignancies. Because of its cytokine synthesis-inhibiting action, interleukin 10 (IL-10) could be a potentially useful molecule to affect leukemic cell growth in such disorders. Chronic myelomonocytic leukemia (CMML) cells spontaneously form myeloid colonies (colony-forming units- granulocyte/macrophage) in methylcellulose, suggesting an autocrine growth factor-mediated mechanism. We studied the effect of recombinant human IL-10 (rhIL-10) on the in vitro growth of mononuclear cells obtained from peripheral blood or bone marrow of patients with CMML. IL- 10 specifically binding to leukemic cells had a profound and dose- dependent inhibitory effect on autonomous in vitro growth of CMML cells. IL-10 significantly inhibited the spontaneous growth of myeloid colonies in methylcellulose in 10/11 patients, and autonomous CMML cell growth in suspension in 5/5 patients tested. Spontaneous colony growth from CMML cells was also markedly reduced by addition of antigranulocyte/macrophage colony-stimulating factor (GM-CSF) antibodies, but not by addition of antibodies against G-CSF, IL-3, or IL-6, IL-10-induced suppression of CMML cell growth was reversed by the addition of exogenous GM-CSF and correlated with a substantial decrease in GM-CSF production by leukemic cells, both at the mRNA and protein levels. Our data indicate that IL-10 profoundly inhibits the autonomous growth of CMML cells in vitro most likely through suppression of endogenous GM-CSF release. This observation suggests therapeutic evaluation of rhIL-10 in patients with CMML.     

Recombinant murine granulocyte macrophage colony-stimulating factor has megakaryocyte colony-stimulating activity and augments megakaryocyte colony stimulation by interleukin 3.

Recombinant murine granulocyte macrophage colony-stimulating factor (rGM-CSF) has been produced in Escherichia coli and purified to homogeneity. GM-CSF has an established role as an in vitro regulator of granulocyte and macrophage colony formation. We have determined that rGM-CSF also has intrinsic activity as a megakaryocyte colony-stimulating factor and that rGM-CSF augments the effect of interleukin 3 (IL-3) on megakaryocyte colony formation. The dose-response curve for megakaryocyte colony induction with rGM-CSF showed plateau megakaryocyte stimulation at 9 ng/ml. When IL-3 (at a plateau dose for megakaryocyte colony induction) was added to rGM-CSF over a 0-22-ng/ml dose range, the resultant megakaryocyte colony stimulation approximated the sum of the levels of stimulation produced by either factor alone. These results establish GM-CSF as a multilineage growth factor with definite megakaryocyte colony-stimulating activity and indicate that both GM-CSF and IL-3 are important in the regulation of megakaryocytopoiesis.     

逆转录病毒介导的GM-CSF在骨髓基质细胞中基因转移与表达

为了探索逆转录病毒介导的GM-CSF在骨髓基质细胞(BMSC)中的基因转移与表达,采用电穿孔法将重组质粒pLXSN/GM和空载体pLXSN转染PA317细胞,经G418筛选,用抗性克隆培养上清液成功地感染了BMSC。经PCR和Southern blot分析证实BMSC基因组中整合有外源NeoR和GM-CSF cDNA,原位杂交显示有较强的GM-CSFmRNA的表达,经增殖法和集落形成法表明转染的BMSC分泌较多的GM-CSF。据此表明,转染的BMSC较未转染BMSC具有更强的支持造血功能,提示BMSC可作为造血功能障碍基因治疗的靶细胞,为GM-CSF基因治疗血液病奠定基础。