Immune gene therapy of experimental mouse brain tumor with adenovirus-mediated gene transfer of murine interleukin-4

Object A hollow fiber catheter was developed to improve the distribution of drugs administered via direct infusion into the central nervous system (CNS). It is a porous catheter that significantly increases the surface area of brain tissue into which a drug is infused. Methods Dye was infused into the mouse brain through convection-enhanced delivery (CED) using a 28-gauge needle compared with a 3-mm-long hollow fiber catheter. To determine whether a hollow fiber catheter could increase the distribution of gene therapy vectors, a recombinant adenovirus expressing the firefly luciferase reporter was injected into the mouse striatum. Gene expression was monitored using in vivo bioluminescent imaging. To assess the distribution of gene transfer, an adenovirus expressing green fluorescent protein was injected into the striatum using a hollow fiber catheter or a needle. Results Hollow fiber catheter–mediated infusion increased the volume of brain tissue labeled with dye by 2.7 times relative to needle-mediated infusion. In vivo imaging revealed that catheter-mediated infusion of adenovirus resulted in gene expression that was 10 times greater than that mediated by a needle. The catheter appreciably increased the area of brain transduced with adenovirus relative to a needle, affecting a significant portion of the injected hemisphere. Conclusions The miniature hollow fiber catheter used in this study significantly increased the distribution of dye and adenoviral-mediated gene transfer in the mouse brain compared with the levels reached using a 28-gauge needle. Compared with standard single-port clinical catheters, the hollow fiber catheter has the advantage of millions of nanoscale pores to increase surface area and bulk flow in the CNS. Extending the scale of the hollow fiber catheter for the large mammalian brain shows promise in increasing the distribution and efficacy of gene therapy and drug therapy using CED.

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Limited efficacy of gene transfer in herpes simplex virus-thymidine kinase/ganciclovir gene therapy for brain tumors

Journal of Neurosurgery ◽

10.3171/jns.2005.102.2.0328 ◽

2005 ◽

Vol 102 (2) ◽

pp. 328-335 ◽

Cited By ~ 14

Author(s):

Piotr Hadaczek ◽

Hanna Mirek ◽

Mitchel S. Berger ◽

Krystof Bankiewicz

Keyword(s):

Gene Therapy ◽

Brain Tumor ◽

Gene Transfer ◽

Thymidine Kinase ◽

Therapeutic Effects ◽

Content Type ◽

Over Time ◽

Fine Print

Object. Low efficacy of gene transfer, transient gene expression, and toxicity of viral vectors are the major hurdles in successful anticancer gene therapy. The authors conducted in vitro (U87MG cell line) and in vivo (xenograft, tumor-bearing rodent model) studies to address the stability of transduction by using the adenoassociated virus serotype-2 (AAV2)—thymidine kinase (TK) vector over time. Methods. Standard methods for cell growth and a ganciclovir (GCV) cytotoxicity assay were applied. The AAV2-TK was infused into implanted tumors in athymic rats via convection-enhanced delivery (CED). Thymidine kinase expression was evaluated through immunohistochemical analysis, and the distribution volumes of the transduced tumors were calculated. Twenty-four hours following the viral infusions, animals were treated with GCV (50 mg/kg intraperitoneally every day for 10 days; six rats) or phosphate-buffered saline (six rats). A rapid decrease in TK expression over time was observed both in vitro and in vivo. A large volume of the tumor (up to 39%) was transduced with AAV2-TK following CED. Administration of GCV resulted in limited therapeutic effects (survival of 25.8 compared with 21.3 days). Conclusions. Rapid elimination of TK expression from dividing tumor cells and focal transduction of the brain tumor were most likely responsible for the limited bystander effect in this approach. Immediate administration of GCV is crucial to assure maximal efficacy in the elimination of cancer cells. In addition, the complete or diffused transduction of a brain tumor with TK may be required for its total eradication.

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