Lysozyme Amyloid for Synthetic RNA Delivery

Background/Objectives: Lysozyme-based amyloid aggregates offer a promising platform for RNA delivery due to their stability, cationic nature, biocompatibility, and ability to form well-defined structures. In this study, we evaluated their potential as drug carriers, focusing on the delivery of polyinosinic-polycytidylic acid (Poly(I:C)), an immunostimulatory synthetic RNA. To validate RNA delivery capability and rule out the possibility that observed effects arose from the lysozyme-Poly(I:C) complex itself, small interfering RNA (siRNA) was also used to verify that the successful delivery of intact and functional RNA was the cause of the observed effects. Methods: The aggregates were characterized by particle size, zeta potential, morphology, and RNA encapsulation efficiency. Results: In vitro studies using RAW 264.7 macrophage-like cells demonstrated that Poly(I:C)-loaded aggregates improved RNA uptake and triggered significant immune activation without inducing toxicity. To further confirm the potential of lysozyme amyloids in RNA delivery, GFP siRNA-loaded aggregates were evaluated in A549-GFP cells. A notable decrease in GFP expression, confirmed through confocal microscopy and flow cytometry, confirmed successful intracellular delivery. Conclusions: These results highlight the potential of lysozyme amyloids as non-viral vectors for RNA delivery, with promising applications in immunotherapy.