美国康奈尔大学John T. G. Pena团队发现，不可逆组织固定可保留胞外囊泡（EV）从而用于原位成像。这一研究成果2019年11月11日在线发表在国际学术期刊《自然—方法学》上。

EV是具有许多生物学功能和病理学联系的分泌型纳米颗粒。无法在固定组织中对EV成像，已成为了解其在健康和患病组织微环境中作用的主要限制。

研究人员发现，与甲醛交联的哺乳动物组织会导致显著的EV损失，这可以通过用1-(3-二甲氨基丙基)-3-乙基碳二亚胺（EDC）进行额外固定来预防，从而可以观察正常和癌症组织的EV。

附：英文原文

Title: Non-reversible tissue fixation retains extracellular vesicles for in situ imaging

Author: Mrinali P. Gupta, Sangeetha Tandalam, Shariss Ostrager, Alexander S. Lever, Angus R. Fung, David D. Hurley, Gemstonn B. Alegre, Jasmin E. Espinal, H. Lawrence Remmel, Sushmita Mukherjee, Benjamin M. Levine, Russell P. Robins, Henrik Molina, Brian D. Dill, Candia M. Kenific, Thomas Tuschl, David Lyden, Donald J. DAmico, John T. G. Pena

Issue&Volume: 2019-11-11

Abstract: Extracellular vesicles (EVs) are secreted nanosized particles with many biological functions and pathological associations. The inability to image EVs in fixed tissues has been a major limitation to understanding their role in healthy and diseased tissue microenvironments. Here, we show that crosslinking mammalian tissues with formaldehyde results in significant EV loss, which can be prevented by additional fixation with 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) for visualization of EVs in a range of normal and cancer tissues.

DOI: 10.1038/s41592-019-0623-4

Source: https://www.nature.com/articles/s41592-019-0623-4