Exosomes are secreted by nanovisicles which are found in body fluids on pathohysicals and normal conditions. The Exosomes was descirebed 30 years ago when a tiny bubbles which have a diameter of 40-100 nm secreted by many of the cells. The structure of membrane is internally coated with a proteins, micro rna and other substances. The observations of exosomes are being investigated for their explotation in the detection of early cancer, disease monitoring and chemotherapeutic response and the development of therapeutics.
In multicellular orgainsms of exosomes and other ev have been present in the tissues which are a biological fluids that contains blood, cerebrospinal fluid and urine. On the size term the exosomes is limited by the parent MVB which are generally seems to be smaller as most lipoproteins which are compare to the smaller than cells.