Geneflow

Abstract

In this thesis, applying viral vectors to the heart will be researched. Optogenetics is a quickly emerging field within microbiology. With a quickly emerging field of research, solutions for applying the viral vectors in a safe, quick and easy way are required.
The current method of genepainting requires a surgical procedure. To apply viral vectors into tissue, the two other main methods of applying viral vectors are encapsulation and microneedling. Encapsulation has been shown in literature to be too novel, with some disadvantages. The decision was made to make microneedles based on the material PVA.
For the production of PVA needles, moulds were made, which are shaped similarly to the design. For this mould production, 3D printing and laser cutting were explored, out of which the 3D printed moulds showed the most reliable characteristics.
The material PVA has been made with two different production processes and materials. The first one is solely PVA, which was solidified by repeated freeze-thaw cycles, and the second one is a mixture of PVA and sucrose solidified by drying the material. The first production has been used to show that the microneedles do penetrate heart tissue; it can be used in combination with viruses, and it has a reliable production method. The second recipe involves mixing sucrose in the PVA, which has been shown to dissolve and decrease in size.
The conclusion shows that for all the aspects of localised viral vector application in the context of optogenetics, PVA microneedles are highly likely to be able to fulfil that role. This will be shown by looking at aspects such as penetration of the heart, solubility of the materials, expression rate after production, and more.