Fagosoom

Fagosoom is a term used in nanomedicine to describe a class of synthetic, phagosome-like vesicles engineered to ferry molecular cargo into the interior of living cells. The name combines phago-, from the Greek phagein meaning to eat, with soma, meaning body, reflecting the vesicle's role as a carrier particle that enters and traverses the cellular interior. Fagosooms are typically constructed as lipid-based nanoparticles that mimic natural phagosomes, featuring a lipid bilayer, surface ligands for targeted cell recognition, and a stabilized internal lumen that can house nucleic acids, proteins, or small molecules.

Development of Fagosooms emerged in the 2010s from research into endosomal escape and intracellular delivery. Early prototypes demonstrated cargo encapsulation and receptor-mediated uptake, with subsequent iterations improving stability, endosomal escape efficiency, and cargo diversity. Modern designs emphasize controlled release, biodegradability, and reduced immunogenicity.

Most Fagosooms are 50-150 nm in diameter, composed of a lipid bilayer with polyethylene glycol (PEG) chains to reduce opsonization, and incorporate pH-responsive peptides or polymers that facilitate endosomal disruption under acidic conditions. Surface ligands can target receptors overexpressed on diseased cells, enabling selective delivery.

After cellular uptake via endocytosis, Fagosooms reside in phagosome-like compartments; they are engineered to fuse with endosomal membranes or escape through proton-sponge mechanisms, releasing cargo into the cytosol. Some designs aim for nuclear delivery or endoplasmic reticulum trafficking, depending on cargo and linker chemistry.

Applications include delivery of siRNA, mRNA, DNA plasmids, CRISPR components, and small-molecule drugs; potential uses span vaccines, oncology, and treatment of genetic diseases. The field remains experimental, with safety, biodistribution, and manufacturability guiding ongoing research.

See also: phagosome, liposome, nanoparticle, endocytosis.