Single cell radiotracer allocation via immunomagentic sorting (scRadiotracing) to disentangle PET signals at cellular resolution
J Nucl Med. 2022 May 19:jnumed.122.264171. doi: 10.2967/jnumed.122.264171. Epub ahead of print. PMID: 35589403.
|Authors/Editors:||Bartos LM, Kunte ST, Beumers P, Xiang X, Wind K, Ziegler S, Bartenstein P, Choi H, Lee DS, Haass C, von Baumgarten L, Tahirovic S, Albert NL, Lindner S, Brendel M.|
With great interest, our independent groups of scientists located in Korea and Germany recognized the use of a very similar methodological approach to quantify the uptake of radioactive glucose (18F-FDG) at the cellular level. The focus of our investigations was to disentangle microglial 18F-FDG uptake. To do so, CD11b immunomagnetic cell sorting (MACS) was applied to isolate microglia cells after in vivo 18F-FDG injection, to allow simple quantification via gamma counter. Importantly, this technique reveals a snapshot of cellular glucose uptake in living mice at the time of injection since 18F-FDG is trapped by hexokinase phosphorylation without further opportunity to be metabolized. Both studies indicated high 18F-FDG uptake of single CD11b positive microglia cells and a significant increase of microglial 18F-FDG uptake when this cell type is activated in the presence of amyloid pathology. Furthermore, another study investigated noticed that MACS after tracer injection facilitated determination of high 18F-FDG uptake in myeloid cells in a range of tumor models. Here, we aim to discuss the rationale of single cell radiotracer allocation via MACS (scRadiotracing) by providing examples of promising applications of this innovative technology in neuroscience, oncology and radiochemistry.