Differentiating extracellular vesicles by environmental disturbance method

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H06255
• Research Category: Grant-in-Aid for Challenging Research (Pioneering)
• Allocation Type: Single-year Grants
• Research Field: Molecular and Genome biology and related fields
• Research Institution: Japanese Foundation for Cancer Research
• Principal Investigator: Shiba Kiyotaka 公益財団法人がん研究会, がん研究所 蛋白創製研究部, 部長 (40196415)
• Project Period (FY): 2017-06-30 – 2020-03-31
• Keywords: 細胞外小胞 / EV / 生体膜 / エクソソーム / 診断学 / 細胞間相互作用 / 膜小胞 / 細胞生物学

Outline of Final Research Achievements

Extracellular vesicles (EVs) in body fluids constitute heterogenous populations, which mirror their diverse parental cells as well as distinct EV-generation pathways. Here, by prolonging ultracentrifugation time to 96 h and fractionating EVs both by floating up or spinning down directions, we allowed 111 EV protein markers from the whole saliva of three healthy volunteers to attain equilibrium. Interestingly, the determined buoyant densities of the markers drifted in a specimen-specific manner, and drift patterns differentiated EVs into at least two subclasses. One class carried classical exosomal markers, such as CD63 and CD81, and the other was characterized by the molecules involved in membrane remodeling or vesicle trafficking. Distinct patterns of density drift may represent the differences in generation pathways of EVs.

Free Research Field

分子生物学

Academic Significance and Societal Importance of the Research Achievements

唾液が含む1,429種のタンパク質のサブクラス化の情報を利用した、各種疾患に対する唾液診断法の開発が、今後進められると期待できる。同定したタンパク質の中には、SLC44A4、PMSA、CEACAM8/CD66b、Serum amyloid A-1 protein (SAA1)といった、広く知られている診断マーカーが含まれており、これらのマーカータンパク質は、細胞外小胞の積荷として体液中の存在している可能性が極めて高く、細胞外小胞にウィンドウを絞ったサンドイッチELISAの開発などにおいても、本研究の結果が利用されていくものと期待できる。