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bioRxiv · 10.1101/2020.03.13.990390

Human-derived NLS enhance the gene transfer efficiency of chitosan

Bitoque, D. B.·Morais, J.·Oliveira, A. V.·Sequeira, R. L.·Calado, S. M.·Fortunato, T. M.·Simao, S.·Rosa da Costa, A. M.·Silva, G. A.
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Abstract

Nuclear import is considered one of the major limitations for non-viral gene delivery systems and the incorporation of nuclear localization signals (NLS) that mediate nuclear intake can be used as a strategy to enhance internalization of exogenous DNA. In this work, human-derived endogenous NLS peptides based on Insulin Growth Factor Binding Proteins (IGFBP), namely IGFBP-3 and IGFBP-5, were tested for their ability to improve nuclear translocation of genetic material by non-viral vectors. Several strategies were tested to determine their effect on chitosan mediated transfection efficiency: co-administration with polyplexes, co-complexation at the time of polyplex formation, and covalent ligation to chitosan. Our results show that co-complexation and covalent ligation of human-derived NLS peptides to chitosan polyplexes yields a 2-fold increase in transfection efficiency. These results indicate that the integration of IGFBP-NLS peptides into polyplexes has potential as a strategy to enhance the efficiency of non-viral vectors.

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Bitoque, D. B., Morais, J., Oliveira, A. V., Sequeira, R. L., Calado, S. M., Fortunato, T. M., Simao, S., Rosa da Costa, A. M., Silva, G. A.. 2020-03-15. Human-derived NLS enhance the gene transfer efficiency of chitosan. https://doi.org/10.1101/2020.03.13.990390

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