The venom of the Eastern coral snake Micrurus fulvius can cause respiratory paralysis in the bitten patient, which is attributable to β-neurotoxins (β -NTx). The aim of this work was to study the biodistribution and lymphatic tracking by molecular imaging of the main β -NTx of M. fulvius venom. β -NTx was bioconjugated with the chelator diethylenetriaminepenta-acetic acid (DTPA) and radiolabeled with the radionuclide Gallium-67. Radiolabeling efficiency was 60%-78%; radiochemical purity ≥92%; and stability at 48 h ≥ 85%. The median lethal dose (LD50) and PLA2 activity of bioconjugated β -NTx decreased 3 and 2.5 times, respectively, in comparison with native β -NTx. The immune recognition by polyclonal antibodies decreased 10 times. Biodistribution of β -NTx-DTPA-67Ga in rats showed increased uptake in popliteal, lumbar nodes and kidneys that was not observed with67Ga-free. Accumulation in organs at 24 h was less than 1%, except for kidneys, where the average was 3.7%. The inoculation site works as a depot, since 10% of the initial dose of β -NTx-DTPA-67Ga remains there for up to 48 h. This work clearly demonstrates the lymphatic system participation in the biodistribution of β -NTx-DTPA-67Ga. Our approach could be applied to analyze the role of the lymphatic system in snakebite for a better understanding of envenoming.
- Coral snake
- Lymphatic absorption
- Molecular imaging
ASJC Scopus subject areas
- Health, Toxicology and Mutagenesis