Chaperonin-Dendrimer Conjugates for siRNA Delivery

Area of Science:

• Biotechnology
• Nanotechnology
• Molecular Biology

Background:

• Group II chaperonins, like thermosome (THS), are protein nanoparticles with internal cavities accessible through pores.
• These structures have potential for encapsulating and delivering therapeutic molecules.
• Developing effective delivery systems for small interfering RNA (siRNA) is crucial for gene therapy.

Purpose of the Study:

• To functionalize THS with poly(amidoamine) (PAMAM) for siRNA conjugation.
• To evaluate the protective effect of THS-PAMAM on siRNA against degradation.
• To assess the efficacy of THS-PAMAM-siRNA in delivering therapeutic payloads into cancer cells.

Main Methods:

• Conjugation of PAMAM to THS to create an anchor for siRNA.
• Loading THS-PAMAM with KIF11 and GAPDH siRNA.
• Incubation of U87 and PC-3 cancer cells with THS-PAMAM-siRNA.
• Modification of THS-PAMAM with the cell-penetrating peptide TAT for enhanced cellular uptake.
• Assessment of siRNA protection against RNase A degradation.

Main Results:

• THS-PAMAM successfully loaded and protected siRNA from RNase A degradation.
• THS-PAMAM-siRNA demonstrated effective delivery into U87 cancer cells, leading to gene silencing.
• Modification with the TAT peptide enabled siRNA delivery and RNA interference in PC-3 cells.

Conclusions:

• THS-PAMAM protein-polymer conjugates are effective siRNA delivery vehicles.
• This approach significantly expands the utility of protein cages in drug delivery.
• THS-PAMAM represents a promising reagent for siRNA transfection and gene silencing therapies.