Development of transfection device from nanoparticles functionalized by LbL for specific delivery of CRISPR/Cas9 system

Abstract

The discovery of CRIPSR/Cas9 has led to great advances in the development of gene therapy due to its substantial efficiency in DNA editing over several cell models, showing, simultaneously, experimental simplicity and low costs. However, there are still barriers to be dealt with in order to fully explore its potential, like a delivery system to target specifically and biologically safe. With this in mind, this project aims at the development of a non-viral vector for gene therapy focused on the CRISPR/Cas9 system. Therefore, gold and polymeric (PLGA, PCL e chitosan) nanoparticles will be prepared and functionalized by Layer-by-Layer technique, which will be responsible for carrying and delivering specifically the Cas9-gRNA complex, as well as the possible co-delivery of DNA double-strands that are used to incorporate new genes in the genome of the cell models (DNA donor). The multilayer system in the proposed vector is responsible for loading, protecting and promoting the controlled release inside the model-cells. Furthermore, the outer layer will have active molecules that interact specifically with membrane receptors on the chosen cell. The model-cell chosen for the transfection experiments is the SKBR (human breast câncer cells) that exhibits HER2 superexpression, which will be targeted by the inclusion of trastuzumab (Herceptin®, specific HER2 antibody) in the last layer of the particle architecture. The target gene of the CRISPR/Cas9 will be the RAS gene, which is the oncogene involved in the signaling pathway of the differentiation and cell proliferation that promotes the appearance of different kinds of tumor cells, including Breast Cancer. (AU)