Protein-encapsulated bio-nanocapsules production with ER membrane localization sequences

Area of Science:

• Biotechnology
• Nanomedicine
• Cellular Biology

Background:

• Bio-nanocapsules (BNCs), derived from Hepatitis B virus surface antigen (HBsAg) L protein, are effective carriers for gene and drug delivery.
• Electroporation, a common method for introducing charged molecules like DNA, is inefficient for protein delivery.
• Existing methods for protein encapsulation into nanoparticles are often complex and may damage the proteins.

Purpose of the Study:

• To develop a novel method for efficient protein encapsulation into bio-nanocapsules (BNCs).
• To overcome the limitations of traditional protein delivery methods, such as electroporation.
• To create a method for protecting therapeutic candidate proteins during encapsulation.

Main Methods:

• A novel approach for BNC preparation was established, involving pre-encapsulation of target proteins during nanoparticle formation.
• Target proteins were associated with the endoplasmic reticulum (ER) membrane using lipidation sequences (ER membrane localization sequences).
• Co-expression of L proteins and membrane-localized target proteins facilitated the budding of protein-encapsulating BNCs from the ER membrane.

Main Results:

• The novel method successfully generated protein-encapsulating BNCs.
• Membrane-localized proteins were automatically enveloped into BNCs during the budding process.
• This method protects proteins and BNCs from potential damage associated with methods like electroporation.

Conclusions:

• The developed method offers a simplified and effective way to encapsulate therapeutic candidate proteins into BNCs.
• This technique enhances the potential of BNCs for targeted protein delivery into various cell types.
• The approach obviates the need for optimizing complex encapsulation conditions and protects sensitive protein cargo.