Development of a Highly Sensitive Device for Counting the Disease-Specific Exosomes in Cancer Patient Sera by Combining Properties of New Optical Disc and Nano-Bead Technologies
August 9, 2018
Keio University School of Medicine
Tokyo Medical University
Japan Agency for Medical Research and Development
A research team at Keio University School of Medicine have developed ExoCounter, an innovative exosome measurement system that integrates optical disc and nano-bead technologies The team was led by Assistant Professor Yasuaki Kabe, Department of Biochemistry, in a joint study with Professor Hiroshi Handa, MD and PhD, at Department of Nanoparticle Translational Research, Tokyo Medical University, and JVCKENWOOD Corporation.
ExoCounter is a new measurement system that allows for precise and easy measurement of the number of disease-specific exosomes. The system binds magnetic nano-beads to disease-specific exosome proteins (surface antigens) on a special optical disc, which is then used to detect the exosome-nanobead complex using an optical disc drive. Exosomes exist mainly in blood and are a type of small particle that is secreted from various cells. ExoCounter renders previously required pretreatments such as exosome purification unnecessary for detecting cancer-specific exosomes secreted from cancer cells and is likely to lead to advances in cancer diagnoses and other applications.
In this study, a large-scale disease cohort study using specimens from the BioBank Japan Project of the Japan Agency for Medical Research and Development (AMED), researchers used an optical disc surface to bind magnetic nano-beads and exosomes that contained HER2 surface antigens secreted from cancer cells, detected the exosome-nanobead complex using ExoCounter, and measured the number of exosomes generated due to cancer. This revealed, for the first time, that the sera of breast and ovarian cancer patients statistically contain a significantly high number of cancer-specific exosomes in which HER2, a known cancer marker, is expressed.
These results are likely to lead to further developments in cancer research, including new cancer diagnoses and cancer treatment methods using exosomes as an indicator.
The study results were published in an early online release of the US scientific journal Clinical Chemistry on Wednesday, July 18, 2018.