Biolistics

Abstract: Keratinization disorders Epidermolytic hyperkeratosis KRT1, KRT10 12 Epidermolytic PPK KRT9 12 Non-epidermolytic PPK KRT16 12 Vohwinkel’s syndrome LOR 31 Ichthyosis bullosa Siemens KRT2e 64 Pachonychia congenita type 1/2 KRT6a, 16, 17 64 X-linked ichthyosis STS 7 Lamellar ichthyosis TGM1 31 Palmoplantar keratoderma GJB2 61 with deafness Erythrokeratodermia variabilis GJB3 60 Darier’s disease ATP2A2 66 Striate palmoplantar keratoderma DSP 2 Striate keratoderma DSG1 62

Abstract: Biolistic transfection is a physical means of transfecting cells by bombarding tissue with high velocity DNA coated particles. We provide a detailed protocol for biolistic transfection of rat hippocampal slices, from the initial preparation of DNA coated bullets to the final shooting of the organotypic slice cultures using a gene gun. Gene gun transfection is an efficient and easy means of transfecting neurons and is especially useful for fluorescently labeling a small subset of cells in tissue slice. In this video, we first outline the steps required to coat gold particles with DNA. We next demonstrate how to line the inside of plastic tubing with the gold/DNA bullets, and how to cut this tubing to obtain the plastic cartridges for loading into the gene gun. Finally, we perform biolistic transfection of rat hippocampal slice cultures, demonstrating handling of the Bio-Rad Helios gene gun, and offering trouble shooting advice to obtain healthy and optimally transfected tissue slices.

Abstract: Although particle-mediated gene transfer technology (gene gun) has been applied for gene transfer to external tissues, the application of this technology to other tissues has met with limited success. Here we report the development of a new design of a gene gun that uses helium discharge to propel DNA-coated gold beads that are suspended in liquid. Higher discharge pressures allow for the delivery of DNA to deeper tissues. Using the new gene gun to deliver a luciferase expression plasmid resulted in higher levels of gene expression in the skin than observed with conventional guns, as well as in subdermal tissues, including subcutaneous tumors. Even when using as little as 125 ng of DNA, gene expression in skin and muscle reached its peak level at 24 hr postbombardment and remained for at least 1 week. The use of a LacZ expression plasmid showed that gene expression was distributed throughout the skin with no observable pathology. The new gene gun was used to deliver a model tumor rejection antigen (a modified human papilloma virus [HPV] E7 gene) to mice. All of the treated animals developed protective immunity against HPV-positive tumors. These results demonstrate that our new design can be used in standard gene gun applications and extends the reach of gene gun technology to tissues that were previously unavailable.