Method to measure and characterize microvesicles in the human body fluids

A non-invasive method to monitor tumor growth, said method having the steps consisting of:

• a) periodically taking a body fluid sample of a patient;
• b) capturing total exosomes of the sample with a primary antibody anti-Rab 5;
• c) detecting tumor related exosomes from the captured total exosomes with a detection antibody;
• d) allowing an enzyme linked secondary antibody to react with the detection antibody;
• e) adding substrate;
• f) detecting the reaction;
• and
• g) drawing a correlation between quantity of detected exosomes and size of the tumor.

A method to quantify and qualify tumor related exosomes in a human body fluid sample, said method having the steps consisting of:

• a) optionally purifying an exosome preparation from the human body fluid sample;
• b) capturing total exosomes of the optionally purified exosome preparation or body fluid sample with primary antibody, said primary antibody being anti-Rab 5b;
• c) detecting tumor related exosomes from the bound exosomes with a detection antibody, said detection antibody being anti-caveolin-1;
• d) allowing an enzyme linked secondary antibody to react with the detection antibody;
• e) adding substrate;
• and
• f) detecting the reaction.

A method to quantify and characterize tumor-related exosomes in an unfractionated human body fluid sample, said method comprising the steps of:

• a) capturing total exosomes from the body fluid sample of about 2 ml or less in volume on an ELISA-plate coated with an anti-Rab5b antibody;
• b) detecting tumor-related exosomes from the captured total exosomes with a detection antibody, said detection antibody being anti-caveolin-1;
• c) allowing an enzyme linked secondary antibody to react with the detection antibody;
• d) adding substrate;
• and
• e) detecting the reaction.