EV imaging

SLAM and EV imaging

EVs were imaged with SLAM with the need of capturing EVs label-free and revealing various metabolic information at the same time. SLAM is capable of imaging isolated EVs derived from cell culture media, urine, serum, and other biofluids. Moreover, SLAM can image EVs inside biological tissues in vivo and ex vivo. SLAM uses 3 optical channels for the EV analysis: THG, 2PF and 3PF. Optical redox ratio FAD/(FAD+NADH) is used for differentiating subpopulations of EVs through metabolic and structural differences. Subpopulation of EVs enable the diagnosis and progression of cancer. NAD(P)H-rich EV ratio is one of the markers for diagnosing and staging cancer of parent cells. Vesicle dynamics in cells are known to be cooperating in carcinogenesis and SLAM can visualize this step. Dynamics of EVs (release, uptake, and migration of EVs) were found in cell and tissue level imaging with SLAM.  

EV imaging with SLAM (a) SLAM images of EVs isolated from cell cultured media. (b) Zoomed-in image of 1 representative EV with 2D (upper) and 3D (lower) visualization maps. Each pixel size is 500 nm. (c) TEM image of EVs. (d) Release of EV from a cell. (e) In vivo visualization of EVs in tumor-bearing rat.

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  • Sun, Y., You, S., Tu, H., Spillman, D.R., Chaney, E.J., Marjanovic, M., Li, J., Barkalifa, R., Wang, J., Higham, A.M. and Luckey, N.N., 2018. Intraoperative visualization of the tumor microenvironment and quantification of extracellular vesicles by label-free nonlinear imaging. Science advances, 4(12), p.eaau5603.
  • You, S., Tu, H., Chaney, E.J., Sun, Y., Zhao, Y., Bower, A.J., Liu, Y.Z., Marjanovic, M., Sinha, S., Pu, Y. and Boppart, S.A., 2018. Intravital imaging by simultaneous label-free autofluorescence-multiharmonic microscopy. Nature communications, 9(1), pp.1-9.
  • Tu, H., Liu, Y., Marjanovic, M., Chaney, E.J., You, S., Zhao, Y. and Boppart, S.A., 2017. Concurrence of extracellular vesicle enrichment and metabolic switch visualized label-free in the tumor microenvironment. Science advances, 3(1), p.e1600675.