Abstract
Purpose :
Mast cells play a crucial role in inflammation by releasing inflammatory mediators, which promote angiogenesis and immune cell recruitment in ocular injury. To primarily target mast cells for interventions in ocular diseases, we exploited ST-2 a cell surface receptor predominantly expressed by mast cells. In this study, we investigated the selective targeting of mast cells using a drug-loaded liposomal delivery via the ligand of ST-2 receptor.
Methods :
We designed a cycloheximide loaded liposomal system which was decorated with ST2 specific ligand to selectively target mast cells. Liposomes were prepared using lipid composition composed of 48:50:2 molar ratio of phosphatidylcholine (PC), cholesterol, and Maleimide polyethylene glycol-di-stearoyl phosphor-ethanolamine (Mal-PEG-DSPE) by thin-film hydration and sonication method. Lipid thin layer was rehydrated with cycloheximide solution in PBS with vertexing, followed by sonication. ST-2 ligand (interleukine-33) was decorated on liposomes using NHS-Mal cross-linking chemistry. The physicochemical characteristics of these liposomes, including their shape, size, drug encapsulation efficiency, and drug release, were evaluated by TEM, Dynamic light scattering (DLS), and dialysis-bag method respectively. Further, we examined the effect of drug-loaded IL33-liposomes on the inflammatory response in human mast cells (LUVA), assessing the expression of pro-inflammatory cytokines through qRT-PCR.
Results :
The drug loaded IL33-liposomes were spherical in shape with particles size of 101.7±18.3 nm with a surface charge of 1.92±0.8 mV. The conjugated liposomes showed significantly higher cellular uptake in human mast cells compared to normal liposomes without ligand. ST2-mediated activation of matured mast cells triggered a proinflammatory response, characterized by an enhanced production of proinflammatory TNF-α (p<00.5) and Interleukin-1β (p<0.05)), which was significantly decreased after treatment with cycloheximide loaded liposomes in 18 h. Further, drug loaded ST2-ligand decorated liposomes induced significant apoptosis in mast cells.
Conclusions :
Our data demonstrate that ST2-ligand decorated liposomes target mast cells and inhibit their inflammatory function, suggesting a potential therapeutic approach for mast cell related diseases.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.