Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12885-018-4418-2/MediaObjects/12885_2018_4418_Fig1_HTML.gif)
Isolation and treatment of Type A and Type B exosomes (a). T-DM1 binds to Type A exosomes prepared from the cell culture medium of HER2-positive breast and gastric cancer cells. Immuno-electron microscopy images showing MCF-7 exosomes treated with T-DM1 (b), SKBR-3 exosomes treated with PBS (c), SKBR-3 exosomes treated with T-DM1 (d), and SNU-216 exosomes treated with T-DM1 (e). T-DM1 is present on exosomes derived from the HER2-positive cell lines (SKBR-3, SNU-216) and treated with T-DM1 (d, e), but not in the controls (b, c). Large arrows point at exosomes, small arrows at immuno-gold labelled T-DM1