Design of liquid crystalline nanoparticles: Linking composition to membrane interactions and siRNA delivery.
LCN-P407 demonstrates superior siRNA uptake and gene silencing compared to LCN-P188, indicating that composition plays a crucial role in the effectiveness of RNA delivery systems.
Where it sits
this study against the rest of the vasopressin corpusSummary and findings
This study evaluated liquid crystalline nanoparticles (LCNs) for siRNA delivery, comparing LCNs formulated with poloxamer 407 (P407) and poloxamer 188 (P188). LCN-P407 demonstrated greater siRNA uptake and gene silencing efficacy in macrophages compared to LCN-P188. Notably, LCN-P407 also showed superior cutaneous penetration in porcine skin models.
Abstract
The clinical translation of small interfering RNA (siRNA) therapeutics critically depends on delivery systems capable of protecting nucleic acids, enabling efficient cellular uptake, and promoting cytosolic release. Liquid crystalline nanoparticles (LCNs) are promising carriers due to tunable internal nanostructure and biocompatibility, yet how composition controls membrane affinity and biological performance remains limited. Here, we compared two cationic reverse-hexagonal LCNs formulated from monoolein, oleic acid, poly(allylamine hydrochloride) and either poloxamer 407 (P407) or poloxamer 188 (P188). Both LCN-P407 and LCN-P188 shared reverse-hexagonal organization, mean diameters of 150-185 nm, low polydispersity (0.09-0.18), positive zeta potentials (10-20 mV), and protection of siRNA from RNase A. Langmuir isotherms and Brewster angle microscopy revealed pronounced adsorption and expansion of DPPC monolayers, with LCN-P188 inducing stronger perturbations, consistent with its higher cytotoxicity (∼20% increase in cell death) relative to LCN-P407. Crucially, siRNA delivered by LCN-P407 showed significantly greater uptake (> 1.7-fold) than that administered by LCN-P188. Functionally, as a proof of concept, we showed that LCN-P407-siTNFα induced robust gene silencing in LPS-stimulated macrophages, reducing TNFα secretion by 1.2-3.5-fold depending on particle concentration and incubation time. LCN-P188-siTNFα produced only delayed and modest reductions (1.3-1.6-fold). In addition, in dermatomized porcine skin, LCN-P407 also exhibited superior cutaneous penetration, delivering siRNA efficiently into the viable epidermis and dermis. Collectively, these results reveal a direct relationship between LCN composition, membrane affinity, and functional performance, providing mechanistic insight for the rational design of LCN-based carriers in RNA therapeutics.
Background
This paper addresses the challenge of delivering siRNA therapeutics effectively, which is crucial for their clinical application. Previous research has highlighted the potential of liquid crystalline nanoparticles (LCNs) as carriers, but the relationship between their composition and biological performance remains underexplored. Understanding how different formulations affect membrane interactions and delivery efficiency is essential for advancing RNA therapeutics.
Methods
The study compared two formulations of cationic reverse-hexagonal LCNs made from monoolein, oleic acid, poly(allylamine hydrochloride), and either poloxamer 407 or poloxamer 188. The primary outcomes measured included siRNA uptake and gene silencing efficacy in LPS-stimulated macrophages. Secondary outcomes included membrane interactions assessed through Langmuir isotherms and Brewster angle microscopy.
Results
LCN-P407 demonstrated > 1.7-fold greater siRNA uptake compared to LCN-P188. In terms of gene silencing, LCN-P407-siTNFα reduced TNFα secretion by 1.2-3.5-fold, while LCN-P188-siTNFα resulted in reductions of 1.3-1.6-fold. The study also noted that LCN-P407 exhibited superior cutaneous penetration into viable epidermis and dermis.
Interpretation
The findings suggest that LCN-P407 is more effective than LCN-P188 for siRNA delivery, aligning with previous literature that emphasizes the importance of formulation in therapeutic efficacy. However, the observed effect sizes, while statistically significant, may not be clinically meaningful without further validation in human studies. Limitations include the lack of detailed statistical analysis and potential confounding factors not addressed in the abstract.
Key findings
- Mean diameters of 150-185 nm, n=Not reported in abstract.
- Positive zeta potentials of 10-20 mV, n=Not reported in abstract.
- LCN-P188 induced ∼20% increase in cell death compared to LCN-P407, n=Not reported in abstract.
- siRNA delivered by LCN-P407 showed > 1.7-fold greater uptake than LCN-P188, n=Not reported in abstract.
- LCN-P407-siTNFα reduced TNFα secretion by 1.2-3.5-fold depending on particle concentration and incubation time, n=Not reported in abstract.
- LCN-P188-siTNFα produced reductions of 1.3-1.6-fold, n=Not reported in abstract.
Limitations
- Sample sizes not reported.
- No specific statistical analyses provided.
- Short follow-up duration.
- In vitro findings may not translate to clinical outcomes.