(C) and (D) Left: representative electron micrograph of exosomes isolated from the medium of BMDMs, BMDM-polarized M2 macrophages, monocytes and monocyte-polarized M2 macrophages are depicted, showing the typical morphology of exosomes. Upper right: the protein levels of CD63 and CD81 were measured by Western blot. Lower left: Nanoparticle tracking analysis showed that most of the particles had a similar size of 50-150 nm in diameter with a peak at around 100 nm. Lower right: LncRNA CRNDE expression levels in different exosomes. Data information: Scale bar= 100 nm. The results shown are from three biological replicates. Data are expressed as mean ± SD. Student's t-test. **P<0.01 vs. BMDMs or monocytes or BMDMs-exo or monocytes-exo. 