The product 'Exorapid-qIC Extracellular Vesicle Immunochromatographic Kit (CD9),' developed by Shimadzu Corporation in cooperation with DAI NIPPON TORYO CO., LTD. (DNT), launched in Japan in July this year. This product is the world's first immunochromatographic kit targeting exosomes, a type of extracellular vesicle (EV).
The kit consists of a solution containing a 'gold nanoplate-labeled antibody (DNT's gold nanoplate bound to an antibody),' an 'immunochromatographic test paper' for capturing exosomes in a sample solution, and a 'washing solution' for cleaning the test paper, and other components. The catalog price is 85,000 yen (excluding tax) for one kit with 33 tests, and the sales target in the first year is 40 kits.
In the joint development, DNT handled the product composition, making use of their knowledge of immunochromatography with precious metal nanoparticles. In terms of product development, Shimadzu was responsible for the selection of EVs to be detected as well as the optimization and evaluation of the exosome detection system.
With this immunochromatographic kit, the cost of one test is approximately 2,600 yen, and because there is no need to install special equipment, the initial cost of the test equipment is reduced. Additionally, inspection time can be shortened to 45 minutes, which is one-fifth of the time required for conventional methods.
EVs, which are lipid-bound vesicles secreted from cells in which the endoplasmic reticulum is under severe stress, are classified as microvesicles, exosomes, or apoptotic bodies depending on their sizes and production mechanisms. Among them, exosomes with a diameter of approximately 100 mm are abundant in blood and urine. Since exosomes contain diverse information about the cells that secrete them, research into their use as a target substance for diagnostic applications is progressing.
For example, exosomes secreted from malignant tumors may be used in early cancer diagnosis.
Exosome-based cancer diagnosis is less invasive to patients than conventional tissue biopsy and cheaper than diagnostic imaging methods such as MRI. Exosomes are also attractive medical materials.
Exosomes secreted from the mesenchymal stem cells (MSCs) used in regenerative medicine are reported to have the ability to heal diseases and wounds. Their administration to human patients in clinical trials has already been started abroad.
Conversely, the research analysis of exosomes requires complicated processes and expensive analytical equipment. For example, the ELISA method takes several productization hours to complete, and the equipment for the nanoparticle tracking analysis (NTA) method is highly expensive. Both Shimadzu and DNT focused on the immunochromatographic method as a quick and easy test method. The immunochromatographic method, which applies capillary phenomenon, has been used in the diagnoses of pregnancy, influenza virus infection, and other symptoms.
With this kit, exosomes are detected in a test paper containing two types of solutions: a sample solution and a solution containing a 'gold nanoplate-labeled antibody (DNT's gold nanoplate bound to an antibody).' If the sample solution contains exosomes, the two lines of 'Test' and 'Control' appear on the test paper.
Since 2017, the two companies have been conducting joint research on the application of DNT-developed precious metal nanoparticles to the life sciences, such as for use in infrared absorption, diagnostic agents, and testing agents. The present productization is a part of this collaboration.
This article has been translated by JST with permission from The Science News Ltd. (https://sci-news.co.jp/). Unauthorized reproduction of the article and photographs is prohibited.