Charge‐Conversional Polyionic Complex Micelles—Efficient Nanocarriers for Protein Delivery into Cytoplasm

Abstract

Special delivery! Polyionic complex (PIC) micelles that contain the charge-conversional moieties citaconic amide or cis-aconitic amide were developed for cytoplasmic protein delivery. The increase of the charge density on the protein cargo helped the stability of the PIC micelles without cross-linking, and the charge-conversion in endosomes induced the dissociation of the PIC micelles to result in efficient endosomal release (see picture).

pH-sensitive degradable nanoparticles for highly efficient intracellular delivery of exogenous protein

“…Polyion complex micelles were also developed for cytoplasmic protein delivery, but the water/oil interfaces that exist when preparing micelles by these methods may lead to protein aggregation and inactivation. 8 Specifically, liposomes without aqueous internal spaces have shown potential for lipophilic drug delivery. Kim et al have developed a liposome composed of lipid and apolipoprotein to mediate targeted delivery of intracellular-acting protein to non-small-cell lung tumors.…”

“…Strong fluorescence was observed inside the cells after 4 hours of incubation ( Figure 6), indicating that EGFP-loaded nanoparticles were efficiently delivered and released protein into the cells. To investigate whether protein had escaped from endosomes, the lysosomes were stained by LysoTracker ® Red (Invitrogen, Carlsbad, CA, USA) as described by Lee et al 8 Images of HeLa cells following incubation for 4 hours with EGFP-loaded nanoparticles showed strong green fluorescence as well as red fluorescence ( Figure 6D), indicating efficient protein release from endosomes. However, for nanoparticles incubated with naked EGFP, green fluorescence could not be detected in the image ( Figure 6G).…”

Positively charged cholesterol–recombinant human gelatins foster the cellular uptake of proteins and murine immune reactions

“…NUNC MaxiSorp 96-well ELISA plates (Nalge Nunc International, Roskilde, Denmark) were coated with 5 µg/mL of OVA in 0.1 M NaHCO 3 Kyoto, Japan), incubated overnight at 4°C and washed with PBS-Tween (PBS-T). The plates were blocked with 3% BSA in PBS for 1 hour at room temperature and washed with PBS-T. After serial dilution in 1% BSA in PBS beginning at a 40-fold dilution, serum samples (100 µL) were added into the wells and the plates were incubated for 1 hour at room temperature.…”

pH-Sensitive Polymeric Micelles for Enhanced Intracellular Anti-cancer Drug Delivery

“…Block copolymers containing ionic and non-ionic water-soluble segments, block ionomers can self-assemble upon interaction with oppositely charged species resulting in the formation of polyion complex (PIC) micelles [4][5][6]. These PIC micelles can incorporate not only oppositely charged polymers [5], but also low molecular mass drugs [6], polynucleotides [7], proteins [8], and imaging agents [9]. These polymeric micelles show preferential accumulation and delivery of drugs and other species to tumor site in the body, due to extended blood circulation and ability to circumvent renal excretion, known as the "enhanced permeability and retention (EPR) effect" [10].…”