Magnetic resonance imaging of melanoma exosomes in lymph nodes

Abstract

Purpose Exosomes are cell derived extracellular nanovesicles that relay molecular signals pertinent to both normal physiologic and disease processes. The ability to modify and track exosomes in vivo is essential to understanding exosome pathogenesis, and for utilizing exosomes as effective diagnostic and therapeutic nanocarriers to treat diseases. Methods We recently reported a new electroporation method that allow exosomes to be loaded with superparamagnetic iron oxide nanoparticles for magnetic resonance tracking. Results Building on this approach, we now demonstrate for the first time using a C57BL/6 mouse model that melanoma exosomes can be imaged in vitro, and within lymph nodes in vivo with the use of standard MRI approaches. Conclusion These findings demonstrate proof of principle that exosome biology can be followed in vivo and pave the way for the development of future diagnostic and therapeutic applications.

Post Isolation Modification of Exosomes for Nanomedicine Applications

“…Using this unique pulse media, the researchers were able to load melanoma exosomes with 5 nm superparamagnetic iron oxide cargo (SPION5) while minimizing EPinduced aggregation effects. Subsequent investigations revealed that SPION5-loaded melanoma exosomes could be tracked to lymph nodes with MRI [29]. Because SPIONs can mediate magnetic hyperthermia, this study highlights the future potential for exosomes to be used as theranostic nanocarriers to simultaneously detect and treat tumor microenvironments using conventional clinical imaging modalities such as MRI.…”

“…Track exosome homing to lymph nodes in mice using MRI [29] DC: Dendritic cell; EAE: Experimental autoimmune encephalitis; LPS: Lipopolysaccharide; MSC: Mesenchymal stem cell.…”

“…(C) Exosome membranes might also be passively loaded with lipophilic fluorescent carbocyanine dyes [9] for imaging and tracking purposes and/or hydrophobic drug cargo such as curcumin [20]. (D) Electroporation can be used to load exosomes internally with hydrophilic cargo such as siRNA [22] or even theranostic superparamagnetic iron oxide cargo [29]. Post isolation modification of exosomes for nanomedicine applications Perspective mice [21].…”

Magnetic resonance imaging of ultrasmall superparamagnetic iron oxide-labeled exosomes from stem cells: a new method to obtain labeled exosomes

“…Recently, nanotechnologies have contributed to advances in in vivo high-resolution imaging to monitor stem cells and exosomes tracking and homing, providing useful insights in their mechanism of action. [18][19][20][21][22][23] To produce a detectable change in signal intensity, cells or exosomes must be labeled with magnetic resonance (MR) contrast agents. In this regard, superparamagnetic iron oxide nanoparticles, which are small crystalline magnetite structures ranging in size from 5 nm to 150 nm, have been widely used to magnetically label stem cells and exosomes.…”

Therapeutic and diagnostic applications of extracellular vesicles

“…The mechanism behind this process remains to be [119]. After footpad injection accumulation of EVs in the lymph nodes was reported [135,136] and intranasal application showed an accumulation in the brain [137,138] in which the delivered anti-inflammatory cargo (i.e. curcumin) could still be detected up to 12 hours after administration [137].…”