Effect of the intracellular localization of a Gd‐based imaging probe on the relaxation enhancement of water protons

Abstract

Gd-HPDO3A has been internalized into rat hepatocarcinoma cells in the cytoplasm (by electroporation) or in intracellular vesicles (by pinocytosis), respectively. In the former case, the observed relaxation rates are likely dependent upon the amount of internalized paramagnetic complex, whereas in the latter case the relaxation enhancement is "quenched" to a plateau value (about 3 s ؊1 ) when the entrapped amount of Gd-chelate is higher than 1 ؋ 10 10 Gd/cell. The observed behavior has been accounted in terms of a theoretical treatment based on equa

Discrepancies between the fate of myoblast xenograft in mouse leg muscle and NMR label persistency after loading with Gd-DTPA or SPIOs

“…For instance, CA diffuses in cytoplasm after electroporation, and in perinuclear vesicles after pinocytosis. 24 Also, as recently pointed out, differential in vivo stability of commercial Gd chelates is another variable to be take into consideration for longer term studies, 40 but should have no role to play in the relative acute process we had been monitoring.…”

“…20,23,24 Grafted on Matrigel structures and subcutaneously implanted, endothelial progenitor cells labeled with Gd-HPDO3A were identified as hyperintensities 14 days after injection. 20 Plugged in mouse kidney, they were visible 24 h after injection.…”

Cytosolic Delivery of Nanolabels Prevents Their Asymmetric Inheritance and Enables Extended Quantitative in Vivo Cell Imaging

“…A third disadvantage of endocytic cell labelling is that the vast majority of the contrast agents are trafficked to the endolysosomes where they are exposed to an acidic and overall degrading environment 26,28 . This can lead to degradation of the contrast agent, lowering the signal intensity, as reported for fluorescent labels [28][29][30] as well as MRI contrast agents [31][32][33] . In addition, it has been reported that nanomaterials trapped in endolysosomal vesicles are not distributed equally over daughter cells upon cell division 30,34,35 .…”

Single Cell Tracking of Gadolinium Labeled CD4+ T Cells by Laser Ablation Inductively Coupled Plasma Mass Spectrometry

“…34,35 Gadolinium internalised via this route is known to localise to endosomes within the perinuclear region of the cell, 34 where subsequent detachment of Gd 3+ from its chelate may occur. 35 Dechelation is expected to be more prevalent for Omniscan than Dotarem.…”