Metabolite Study and Structural Authentication for the First-in-Human Use Sphingosine-1-phosphate Receptor 1 Radiotracer.

ABSTRACT: The sphingosine-1-phosphate receptor 1 (S1PR1) radiotracer [¹¹C]CS1P1 has shown promise in proof-of-concept PET imaging of neuroinflammation in multiple sclerosis (MS). Our HPLC radiometabolite analysis of human plasma samples collected during PET scans with [¹¹C]CS1P1 detected a radiometabolite peak that is more lipophilic than [¹¹C]CS1P1. Radiolabeled metabolites that cross the blood-brain barrier complicate quantitative modeling of neuroimaging tracers; thus, characterizing such radiometabolites is important. Here, we report our detailed investigation of the metabolite profile of [¹¹C]CS1P1 in rats, nonhuman primates, and humans. CS1P1 is a fluorine-containing ligand that we labeled with C-11 or F-18 for prec

SUBMITTER: Qiu L 

PROVIDER: S-EPMC11103254 | biostudies-literature | 2024 May

REPOSITORIES: biostudies-literature