Differentialin vivobiodistribution of131I-labeled exosomes from diverse cellular origins and its implication in the theranostic application

Exosomes are critical mediators of intercellular crosstalk and regulator of cellular/tumor microenvironment. Exosomes have great prospects for clinical application as theranostic and prognostic probe. Nevertheless, the advancement of the exosomes research has been thwarted by limited knowledge elucidating the most efficient isolation method and theirin vivotrafficking. Here we have showed that combination of two size-based methods using 0.20 µm syringe filter and 100k centrifuge membrane filter followed by ultracentrifugation method yields a greater number of uniform exosomes. We also demonstrated the visual representation and quantification of differentialin vivodistribution of radioisotope131I-labelled exosomes from diverse cellular origins, e.g., tumor cells with or without treatments (HET0016 and GW2580), myeloid-derived suppressor cells and endothelial progenitor cells. We also determined that the distribution was dependent on the protein/cytokine contents of the exosomes. The appliedin vivoimaging modalities can be utilized to monitor disease progression, metastasis, and exosome-based targeted therapy.AbbreviationsbFGFbasic fibroblast growth factorCSF1Rcolony stimulating factor 1 receptorCTcomputed tomographyCTLA4cytotoxic T-lymphocyte-associated protein 4EGFepidermal growth factorEMTepithelial to mesenchymal transitionEVsextracellular vesiclesEPCsendothelial progenitor cellsFasLFas ligandG-CSFgranulocyte-colony stimulating factorGM-CSFgranulocyte-macrophage colony-stimulating factorHGFhepatocyte growth factorHSPheat shock proteinICAM-1intercellular adhesion molecule 1IFN-gammainterferon gammaIL – 1betainterleukin-1 betaIL – 1rainterleukin-1 receptor antagonistIL – 2interleukin-2IL – 4interleukin-4IL – 6interleukin-6IL – 7interleukin-7IL – 10interleukin-10IL – 12interleukin-12IL – 13interleukin-13IL – 17interleukin-17KCkeratinocyte-derived chemokineLIXlipopolysaccharide-induced CXC chemokineM-CSFmacrophage colony-stimulating factorMCP-1monocyte chemoattractant protein 1MDCmacrophage-derived chemokineMDSCsmyeloid derived suppressor cellsMFPmammary fat padMIP-1αmacrophage-inflammatory protein-1alphaMMP-2matrix metalloproteinase-2MRImagnetic resonance imagingNISsodium iodide symporterNTAnanoparticle tracking analysisPETpositron emission tomographyPF-4platelet factor 4RANTESregulated on activation, normal T cell expressed and secretedROIsregion of interestSDF-1αstromal cell-derived factor-1SEMstandard error of the meanSPECTsingle-photon emission computed tomographySCFstem cell factorTAMstumor-associated macrophagesTEMtransmission electron microscopyTIMP 2tissue inhibitors of metalloproteinases 2TLPCthin layer paper chromatographyTMEtumor microenvironmentTNF-αtumor necrosis factor-αTSLPthymic stromal lymphopoietinUCultracentrifugationVEGF-Avascular endothelial growth factor AVEGFR2vascular endothelial growth factor receptor 2.