Complex carriers of affibody-displaying bio-nanocapsules and composition-varied liposomes for HER2-expressing breast cancer cell-specific protein delivery

Abstract

A bio-nanocapsule (BNC), a hollow particle composed of hepatitis B virus (HBV) surface antigen (HBsAg), and liposome (LP) conjugation method (BNC/LP) has been recently developed by . The BNC/LP complex carrier could successfully deliver fluorescence-labeled beads (100 nm) into liver cells. In this study, we report the promising delivery of proteins incorporated in the complex carriers, which were prepared by the BNC/LP conjugation method with specificity-altered BNC and composition-varied LPs. The specificity-altered BNC, Z_HER2-BNC was developed by replacing the hepatocyte recognition site of BNC with Z_HER2 binding to HER2 receptor specifically. Using green fluorescent protein (GFP; 27 kDa) and cellular cytotoxic protein (exotoxin A; 66 kDa) for the delivery, we herein present the impact of different charges attributed to the composition of the LP on specific cell targeting and cellular uptake of the complex carriers. In addition, we demonstrate that the mixture prepared by mixing LPs with helper lipid possessing endosomal escaping ability boosts the functional expression of the cellular cytotoxic exotoxin A activity specifically. Finally, we further show the blending ratio of the LP mixture and Z_HER2-BNC is a critical factor in determining the highly-efficient expression of the cytotoxic activity of exotoxin A.

Keyword::

• Controlled release
• drug delivery
• drug targeting
• Hepatitis B virus
• in vitro model
• liposomes
• nanoparticles

Acknowledgements

The authors would like to thank Prof. Shun’ichi Kuroda for his advice on the BNC/LP conjugation method. This work was supported in part by a Special Coordination Fund for Promoting Science and Technology, Creation of Innovative Centers for Advanced Interdisciplinary Research Areas (Innovative Bioproduction Kobe) from the Ministry of Education, Culture, Sports and Technology (MEXT), and Science Research Grants from the Ministry of Health, Labour and Welfare, Japan.

Declaration of interest

The authors report no declaration of interest.