Biological Studies

As outlined in the video, the radiopeptide prepared and tested in the Radio-Lab is first tested at the cellular level in the in vitro studies facilities. The cells expressing the GPCR-target have been cultured in a dedicated “cell-culture” room and prepared for the study on the previous day. Competition or saturation binding studies will reveal the affinity of the new agent for its cognate GPCR. Internalization studies will reveal if and how fast it enters the cell. Internalization usually matches an agonist profile.

Studies at the animal level are conducted in the anatomy room. Metabolic stability studies are performed in healthy mice provided by the animal house of NCSR “D” a day before. The radiopeptide is injected in the tail vein of mice (treated or not with protease-inhibitors) and after euthanasia, blood or urine are collected, processed and returned to the Radioanalytical Lab for detecting radiometabolite formation.

Likewise, biodistribution of the radiopeptide or preparation of animals for imaging is conducted in the anatomy room. Immunosuppressed mice provided by the animal house of NCSR “D” have been previously inoculated with a suspension of cells expressing or not (negative controls) the relevant GPCR for tumor induction. The animals are kept in a suitable facility under sterile conditions till tumors have grown to the right size. After injection of the radiopeptide, the animals are euthanized and biodistribution or imaging are conducted.

Suitably equipped and dedicated labs for the above-described biological studies are available, including: i) the cell culture room, ii) the room for the maintenance of immunosuppressed animals, iii) the room for in vitro studies of radiopeptides and iv) small-animal anatomy room for in vivo studies of radiopeptides. Rooms ii) and iv) are licensed and supervised by National Authorities (Ministry of Agriculture) for abiding to European guidelines and the Helsinki convention for the well-being of laboratory animals. All animals protocols are likewise approved by the Authorities and only trained and authorized personnel participates in animal experiments.

Furthermore, experiments in rooms iii) and iv) involve open radioactive sources. Handling of radioactive material and waste-management has to abide to international rules and guidelines. Accordingly, these two rooms of Molecular Radiopharmacy are licensed and supervised by the Greek Atomic Energy Commission. Accordingly, all manipulations are performed by trained and authorized personnel behind suitable protecting shielding.

The labs are well-equipped with radioactivity counters, multi-sample cell harvester, homogenizers, centrifuges, incubators, microscope, laminar flow cabinets, freezers, special deep-freeze containers for cell storage, balances.