Autologous, Orthotopic Thyroid Follicular Cell Transplantation: A Surgical Component of Ex Vivo Somatic Gene Therapy

1993 ◽  
Vol 108 (1) ◽  
pp. 51-62 ◽  
Author(s):  
Bert W. O'Malley ◽  
Milton J. Finegold ◽  
Fred D. Ledley

Ex vivo strategies for somatic gene therapy involve the harvest of primary cells from patients, the transfer of novel genetic material into these cells in cell culture, and reimplantation of the genetically engineered cells back into patients. In consideration of methods for targeting somatic gene therapy to the thyroid, we have studied the autologous, orthotopic transplantation of thyroid follicular cells in a canine model. Using the fluorescent dye Dil, we were able to stain follicular cells in vitro before transplantation and then follow the pattern of engraftment through histologic sectioning and microscopy up to 14 days after transplantation. The transplantations involved the direct injection of intact and disrupted follicles into a remaining thyroid lobe after cell harvest from the contralateral lobe. We also demonstrated engraftment of individual follicular cells recovered from primary monolayer cultures. Histologic studies revealed the presence of transplanted cells and follicles as well as focal regions of granulomatous reaction in close relation to the engrafted material. These studies demonstrate the feasibility of autologous, orthotopic transplantation of thyroid follicular cells. This method is an essential component of ex vivo strategies for targeting somatic gene therapy to the thyroid gland.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 196-196
Author(s):  
Sandra Pilat ◽  
Sebastian Carotta ◽  
Bernhard Schiedlmeier ◽  
Kenji Kamino ◽  
Andreas Mairhofer ◽  
...  

Abstract In the context of somatic gene therapy of the hematopoietic system, transplantation of molecularly defined and, hence, “safe” clones would be highly desirable. However, techniques which allow gene targeting, subsequent in vitro selection and clonal expansion are only available for embryonic stem (ES) cells. After in vitro differentiation, some of their progeny cells are capable of mediating long term hematopoietic repopulation after transplantation into immunodeficient recipient mice, in vivo. This is especially efficient when the homeodomain transcription factor HOXB4 is ectopically expressed (1). We have recently shown that HOXB4-ES-cell derivatives behave similar to bone marrow cells also expressing this transcription factor ectopically, both in vitro and in vivo (2). Here we demonstrate that long term repopulation (>6 months) in Rag2(−/−)γ C(−/−) mice can be achieved with ES-cell derived hematopoietic cells (ES-HCs) obtained from single, molecularly characterized ES-clones, in which the insertion sites of the retroviral expression vector had been defined. Clones expressing HOXB4 above a certain level showed a high extent of chimerism in the bone marrow of transplanted mice (average 75%; range 45–95%, n=4) whereas ES-HC clones expressing lower levels only repopulated with very low efficiency (average 2.5% chimerism, range 1–4%, n=6 mice). These results suggest that the capability of long-term repopulation, in vivo, is highly dependent on the expression levels of HOXB4 in the transplanted clones. Only mice reconstituted with ES-HC clones expressing high amounts of HOXB4 and thus showing substantial chimerism, recapitulated the morphohistological phenotype observed in polyclonally reconstituted mice. This included the bias towards myelopoiesis, “benign” myeloid proliferation in spleen and the incompatibility of HOXB4 expression with T-cell poiesis (2). In summary, we demonstrate that repopulation of the hematopoietic system can be achieved with preselected clones of genetically manipulated stem cells in which a) the insertion site of the retroviral (gene therapy) vector has been characterized prior to transplantation and b) in which ectopic HOXB4 has to be expressed above a certain threshold level. Thus, ES cells carry the potential for performing safe somatic gene therapy when using integrating gene therapy vectors. Nevertheless, advanced cell therapy will certainly require the expression of HOXB4 in a regulated manner to avoid unwanted effects such as disturbed lineage differentiation.


Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 494-494 ◽  
Author(s):  
Sandra Pilat ◽  
Carotta Sebastian ◽  
Schiedlmeier Bernhard ◽  
Modlich Ute ◽  
Kamino Kenji ◽  
...  

Abstract In the context of somatic gene therapy of the hematopoietic system, transplantation of molecularly defined and, hence, “safe” clones would be highly desirable. However, techniques which allow gene targeting, subsequent <i>in vitro</i> selection and clonal expansion are only available for embryonic stem (ES−) cells. Previously, it has been shown that <i>in vitro</i> differentiated ES-cells engraft when ectopically expressing HOXB4, but it remained unclear whether these cells could fully resemble adult bone marrow function after transplantation<sup>1</sup>. We here demonstrate for the first time the functional equivalence of <i>in vitro</i> differentiated ES-cells and adult bone marrow cells mediated by HOXB4. Differentiated ES-cells expressing HOXB4 from a retroviral vector and grown <i>in vitro</i> for 20 days, recapitulated the growth and differentiation properties of adult bone marrow cells after transplantation into Rag2<sup>(−/−)</sup>γC<sup>(−/−)</sup> and C57Bl/6J recipient mice. Furthermore, we show that the amount of ectopically expressed HOXB4 influences differentiation in both systems in a similar manner. HOXB4 enforced myeloid and suppressed T-lymphoid development over a wide range of expression levels, whereas only high expression levels of HOXB4 were detrimental for erythroid development (P-values for C57Bl/6J mice, Student’s t-test, 2-sided: CD3 + : eGFP<sup>low</sup> vs. HOX<sup>low</sup> = 0.003; eGFP<sup>high</sup> vs. HOX<sup>high</sup> = 0.021; Ter119 +: eGFP<sup>low</sup> vs. HOX<sup>low</sup> = 0.920; eGFP<sup>high</sup> vs. HOX<sup>high</sup> = 0.0122; HOX<sup>low</sup> vs. HOX<sup>high</sup> = 0.005). Incompatibility of high levels of HOXB4 expression with erythroid differentiation was also directly demonstrated using a recently described <i>in vitro</i> ES-cell differentiation system<sup>2</sup>. Histological analysis of the “HOXB4-transplanted” mice revealed increased granulopoiesis both in sternal bone marrow and in spleen sections. However, all stages of granulocytic differentiation were present and neither were immature cells detected in the periphery nor was leukemic infiltration detected in other organs. Hence, none of the animals became leukemic during the observation period. In summary, ES-cells should be considered a promising alternative to bone marrow stem cells carrying the potential of safe somatic gene therapy, provided that human ES-cells can be similarly manipulated. Nonetheless, advanced cell therapy will certainly require regulated expression of HOXB4 to avoid unwanted effects such as disturbed lineage differentiation. This work was supported by the German Research Foundation (KL1311/2-3 and 2-4), German Cancer Aid (10-1763-OS5) and the Austrian Industrial Research Promotion Fund (808714).


1991 ◽  
Vol 5 (3) ◽  
pp. 423-432 ◽  
Author(s):  
Charles Hesdorffer ◽  
Dina Markowitz ◽  
Maureen Ward ◽  
Arthur Bank

1995 ◽  
Vol 6 (2) ◽  
pp. 165-175 ◽  
Author(s):  
Ayman Al-Hendy ◽  
Gonzalo Hortelano ◽  
Gloria S. Tannenbaum ◽  
Patricia L. Chang

2021 ◽  
Author(s):  
Moataz Dowaidar

Gene therapy involves transferring genetic material (DNA or RNA) to repair, regulate or replace genes to cure a disease. One of the most crucial barriers is successful delivery of the targeted gene into the target tissue. Various vector-based approaches have been developed to deliver the transgene to the target cells. In different cancers, numerous of these vectors are being developed for purposes such as immunotherapy, suicide gene therapy, microRNA (miRNA) focused treatment, oncogene silencing, and gene editing using CRISPR/Cas9. This article reviews several alternatives to cancer gene therapy, as well as their preclinical and clinical outcomes, possible limitations, and overall therapy effects. Ways of delivering cancer gene therapy include direct methods for introducing genetic material. Nonviral vectors are easy to manufacture and may be chemically modified to increase their usefulness. Cationic polymers such as Poly-L-Lysine (PLL) and Polyethylenimine (PEI-SS) are the most extensively used polycationic polymers for gene transfer, particularly in vitro. Many RNAi-based therapeutic approaches are approaching the clinical stage, and nanocarriers are likely to play a crucial role in treating specific cancers. In the previous decade, non-viral approaches were used in more than 17 percent of all gene therapy trials. The message is that this is a safe and effective technique for transferring genes to cancer patients who need it to be a safe, successful therapy. Exosomes were developed to carry oncogene-specific short interfering RNA. Sushrut and colleagues revealed that exosomes provide superior carriers of short RNA and prevent tumor growth than liposomes. Inhalation-based gene therapy (aerosol-mediated gene delivery) has gained pace as a feasible treatment approach, especially for lung cancer. Because the intended transgene is steered to specific cells/tissues, this should further increase therapeutic efficiency.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Tao Wang ◽  
Yigang Wang ◽  
Dongsheng Zhang ◽  
Tiemin Zhao ◽  
Atif Ashraf ◽  
...  

We hypothesize that CXCR4 + -MSCs penetrate and proliferate in infracted heart by releasing collagen degrading enzymes. We genetically engineered male mouse MSCs using ex vivo adenoviral transduction for over-expression of CXCR4/GFP or GFP alone. MSCs (G-I) or CXCR4 + -MSCs (G-II) or CXCR4 + -MSCs treated with epigallocarechin gallate (EGCG, 50μg/ml), a MT1-matrix metalloproteinases (MMPs) inhibitor (G-III) or CXCR4 + -MSCs with AMD3100 (5 μg/mL), a CXCR4-selective antagonist (G-IV). A Trans-Matrigel Chemoinvasion Assay was used to evaluate the ability of MSCs to cross the basement membrane. MMPs were analyzed by Western blot and MMP antibody staining. Sex mismatched MSCs were infused into female mice via a tail vein injection 3 days after MI. Mice in G-III were treated with EGCG (100 mg/kg, oral gavage, daily for 2 weeks) to inhibit MMPs and G-IV was treated with AMD3100 (1 mg/kg, i.p. given continually for 6 days after MI). LV fibrosis was detected by Picrosirius red staining. Echocardiography was performed at 4 weeks after MI and hearts were harvested for histological analysis. In vitro, cell migration was significantly higher in G-II in the presence of SDF-1α as compared with other groups, ( p <0.01). EGCG or AMD3100 markedly prevented this response. MMP-9 and MT1-MMP were upregulated significantly only in G-II (p<0.01) exposed to hypoxia. Infiltration of GFP and Y chromosome positive cells in the peri- or infarct area was increased significantly in G-II. CXCR4 + -MSCs penetrated more effectively into the infarcted region and survived in the ischemic environment as compared to control group. These effects were reduced with EGCG or AMD3100. The ventricular remodeling and interstitial fibrosis were also reduced in G-II but not in other groups. G-II also had less LV dilation (diastolic dimension 4.9±0.2 vs. 6.2±0.3 mm, p<0.05), EF (62±3 vs. 44±4%, p<0.05). Infarct size (31±3.8 vs 43±4.7% of LV, p<0.05) and collagen area fraction (16±2 vs. 28±4 %, p<0.05) were significantly reduced in G-2 compared to G-I. Under hypoxic conditions MMPs were upregulated in CXCR4 + -MSCs which crossed the basement membrane by releasing enzymes leading to breakdown or reduction of scar formation thus facilitating cell homing and proliferation.


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