PET Imaging of GPR44 by Antagonist [11C]MK-7246 in Pigs.

Cheung P, Zhang B, Puuvuori E, Estrada S, Amin MA, Ye S, Korsgren O, Odell LR, Eriksson J, Eriksson O

Biomedicines 9 (4) - [2021-04-16; online 2021-04-16]

A validated imaging marker for beta-cell mass would improve understanding of diabetes etiology and enable new strategies in therapy development. We previously identified the membrane-spanning protein GPR44 as highly expressed and specific to the beta cells of the pancreas. The selective GPR44 antagonist MK-7246 was radiolabeled with carbon-11 and the resulting positron-emission tomography (PET) tracer [11C]MK-7246 was evaluated in a pig model and in vitro cell lines. The [11C]MK-7246 compound demonstrated mainly hepatobiliary excretion with a clearly defined pancreas, no spillover from adjacent tissues, and pancreatic binding similar in magnitude to the previously evaluated GPR44 radioligand [11C]AZ12204657. The binding could be blocked by preadministration of nonradioactive MK-7246, indicating a receptor-binding mechanism. [11C]MK-7246 showed strong potential as a PET ligand candidate for visualization of beta-cell mass (BCM) and clinical translation of this methodology is ongoing.

Olof Eriksson

SciLifeLab Fellow

PubMed 33923731

DOI 10.3390/biomedicines9040434

Crossref 10.3390/biomedicines9040434

pmc: PMC8073488
pii: biomedicines9040434

Publications 9.5.0