eksosomien

Eksosomien, also known as exosomes, are a class of extracellular vesicles that cells release into the surrounding environment. They are typically 30–150 nanometers in diameter and are formed within multivesicular bodies, which fuse with the plasma membrane to discharge the vesicles. Because they originate from the endosomal sorting complex required for transport (ESCRT) machinery, exosomes carry a distinct molecular composition that reflects their cell of origin.

The vesicular membrane is enriched in cholesterol, sphingomyelin and a variety of tetraspanins such as CD9, CD63 and CD81, which are frequently used as exosomal markers. The interior of an exosome can contain proteins, messenger RNAs, microRNAs and lipids that are selectively packaged during biogenesis. These cargo molecules enable exosomes to function as intercellular communicators, delivering genetic and protein information that influences recipient cells’ behavior.

In physiological contexts, exosomes contribute to immune surveillance, blood coagulation and neuronal signaling. Pathologically, tumor cells release exosomes that modulate the microenvironment, promote angiogenesis and suppress anti‑tumor immunity. In addition, exosomes secreted during viral infection can transfer viral RNA and proteins, facilitating virus spread. Because of their presence in easily accessible body fluids such as blood, urine and saliva, exosomes are being investigated as diagnostic biomarkers for a range of diseases, including cancer, neurodegeneration and cardiovascular disorders.

Research into exosome isolation techniques (ultracentrifugation, size‑exclusion chromatography, immuno‑capture) and characterization methods (nanoparticle tracking analysis, electron microscopy, flow cytometry) continues to refine our understanding of their biology and therapeutic potential. Exosome‑based therapeutics, such as engineered vesicles carrying drugs or RNA therapeutics, are an emerging area of clinical development.