Interactions of polymerized phospholipid vesicles with cells. Uptake, processing and toxicity in macrophages

Area of Science:

• Biochemistry
• Cell Biology
• Materials Science

Background:

• Phosphatidylcholine vesicles are widely studied for drug delivery.
• Understanding vesicle-macrophage interactions is crucial for developing effective therapies.
• Polymerization of vesicle components can alter their properties and biological interactions.

Purpose of the Study:

• To investigate the uptake of photopolymerized bis(1,2(methacryloyloxy)dodecanoyl)-L-alpha-phosphatidylcholine (DPL) vesicles by mouse peritoneal macrophages.
• To compare the uptake and toxicity of polymerized DPL vesicles with conventional phosphatidylcholine vesicles.
• To elucidate the mechanisms underlying the interaction between macrophages and polymerized DPL vesicles.

Main Methods:

• In vitro study using mouse peritoneal macrophages.
• Utilized radiolabeled DPL vesicles for uptake quantification.
• Investigated blocking effects using unlabeled vesicles in fluid and gel states, and charged vesicles.
• Assessed vesicle toxicity to macrophages.

Main Results:

• Photopolymerized DPL vesicles exhibited significantly higher and faster uptake by macrophages compared to conventional phosphatidylcholine vesicles.
• Uptake was not inhibited by fluid-state or gel-state unlabeled phosphatidylcholine vesicles.
• Solid-phase negatively charged vesicles partially blocked DPL vesicle uptake, suggesting specific interactions.
• Polymerized DPL vesicles demonstrated significantly lower toxicity to macrophages than non-polymerized DPL vesicles.

Conclusions:

• Photopolymerization enhances the uptake of DPL vesicles by macrophages.
• Polymerized DPL vesicles represent a less toxic alternative to conventional or non-polymerized vesicles.
• These findings suggest potential applications for photopolymerized DPL vesicles in targeted drug delivery and immunomodulation.