In vitro autoradiography of carcinoembryonic antigen in tissue from patients with colorectal cancer using multifunctional antibody TF2 and (67/68Ga)-labeled haptens by pretargeting.

The carcinoembryonic antigen (CEA) was visualized in vitro in tissue from patients with colorectal cancer with trivalent bispecific antibody TF2 and two hapten molecules, [(67/68)Ga]Ga-IMP461 and [(67/68)Ga]Ga-IMP485 by means of pretargeting. Colorectal cancer tissue samples obtained from surgery at Uppsala University Hospital, were frozen fresh and cryosectioned. The two hapten molecules comprising 1,4,7-triazacyclononanetriacetic acid chelate moiety (NOTA) were labeled with (67)Ga or (68)Ga.

(68)Ga-Labeling of RGD peptides and biodistribution.

Several peptides comprising Arg-Gly-Asp (RGD) domain and macrocyclic chelator were labeled with (68)Ga for the imaging of angiogenesis. The analogues varied in peptide constitution, linker and chelator type. The labeling efficiency did not vary with the peptide constitution and linker type, but depended on the chelator type.

68Ga-autoclabeling of DOTA-TATE and DOTA-NOC.

Introduction: A new method combining (68)Ga-labeling and steam sterilization, here called autoclabeling, has been evaluated for two somatostatin receptor binding tracers used for positron emission tomography (PET) imaging of neuroendocrine tumors; DOTA-TATE and -NOC.

Methods: The two peptides DOTA-TATE and -NOC were labeled with (68)Ga by heating for 15 min at 121°C in the presence of acetate buffer at pH 4.3.

Preclinical evaluation of a 68Ga-labeled biotin analogue for applications in islet transplantation.

Introduction: Islet transplantation is a promising treatment for type 1 diabetes mellitus, but the fate of the cells after intraportal infusion is unclear. It is therefore imperative to develop novel techniques for noninvasive imaging and quantification of events following islet transplantation.

Methods: Small islet-like microbeads, avidin-covered agarose resins (AARs), were used as a model system for islet transplantation.

68Ga-labeling of biotin analogues and their characterization.

Biotin- and (68)Ga-based tracers have been suggested as tools that could be used to monitor the survival of avidin-coated islets of Langerhans isolated from pancreas and used in transplantation, i.e., to liver.