Intracellular localisation of proteins to specific cellular areas by nanocapsule mediated delivery

Abstract

Nanocapsules are promising carriers with great potential for intracellular protein transport. Although many studies have intended to improve cell uptake efficacy, there is an increasing interest in understanding of subcellular distribution of cargoes inside cells, which is essential for purposeful delivery of biomolecules into specific sites within cells. Herein, we interrogate the intracellular localisation of exogenous proteins, including fluorescein isothiocyanate (FITC)-labelled bovine serum albumin (BSA) and green fluorescent protein (GFP), mediated by specially designed nanocapsules. The results show that the designed nanocapsules can deliver the two types of fluorescent proteins into different cellular destinations (cytosol, nucleus or the whole cell), depending on the composition of nanocapsules. Meanwhile, several impact factors that influence the distribution of proteins in cells have also been investigated, and the results suggest that the localisation of capsule-mediated proteins in cells is strongly affected by the surface properties of nanocapsules, the types of stabilisers and proteins, and environmental temperatures. The rational control of intracellular localised delivery of exogenous proteins as we demonstrated in this study might open new avenues to obtain desired magnitude of drug effects for modulating cell activity.

Keywords:

• Nanocapsule
• protein delivery
• intracellular localisation
• fluorescence

Acknowledgements

This work is supported by the grants from the Natural Science Foundation of China (81273416), the Scientific Research Foundation for Returned Scholars, Ministry of Education of China (2012-940), and the Fundamental Research Funds for the Central Universities (XDJK2013A030) and the Program for New Century Excellent Talents in University, Ministry of Education of China. H.W. also acknowledges the support from Chongqing Institute of Green and Intelligent Technology for Startup Foundation for Advanced Talents, Chongqing Science and Technology Commission (cstc2015jcyjiA10057 and YJ500061LH1), and the Chinese Academy of Sciences for a Key Scientific Instrument and Equipment Development Project and for the program for Young Talented Scientists (R52A500Z10).

Disclosure statement

No potential conflict of interest was reported by the authors.