Intraoperative visualization of nerves using a myelin protein-zero specific fluorescent tracer.

Background: Surgically induced nerve damage is a common but debilitating side effect in oncological surgery. With the aim to use fluorescence guidance to enable nerve-sparing interventions in future surgery, a fluorescent tracer was developed that specifically targets myelin protein zero (P0).

Results: Truncated homotypic P0 protein-based peptide sequences were C-terminally functionalized with the far-red cyanine dye Cy5.

Image-Guided Surgery: Are We Getting the Most Out of Small-Molecule Prostate-Specific-Membrane-Antigen-Targeted Tracers?

Expressed on virtually all prostate cancers and their metastases, the transmembrane protein prostate-specific membrane antigen (PSMA) provides a valuable target for the imaging of prostate cancer. Not only does PSMA provide a target for noninvasive diagnostic imaging, e.g.

Hybrid Tracers Based on Cyanine Backbones Targeting Prostate-Specific Membrane Antigen: Tuning Pharmacokinetic Properties and Exploring Dye-Protein Interaction.

Prostate cancer surgery is currently being revolutionized by the use of prostate-specific membrane antigen (PSMA)-targeted radiotracers, for example, Tc-labeled PSMA tracer analogs for radioguided surgery. The purpose of this study was to develop a second-generation Tc-labeled PSMA-targeted tracer incorporating a fluorescent dye. Several PSMA-targeted hybrid tracers were synthesized: glutamic acid-urea-lysine (EuK)-Cy5-mas, EuK-(SO)Cy5-mas, EuK-Cy5(SO)-mas, EuK-(Ar)Cy5-mas, and EuK-Cy5(Ar)-mas; the Cy5 dye acts as a functional backbone between the EuK targeting vector and the 2-mercaptoacetyl-seryl-seryl-seryl (mas) chelate to study the dye's interaction with PSMA's amphipathic entrance funnel.

Click Chemistry in the Design and Production of Hybrid Tracers.

Hybrid tracers containing both fluorescent and radioactive imaging labels have demonstrated clinical potential during sentinel lymph node procedures. To combine these two labels on a single targeting vector that allows tumor-targeted imaging, end-labeling strategies are often applied. For αβ-integrin-targeting hybrid tracers, providing an excellent model for evaluating tracer development strategies, end-labeling-based synthesis provides a rather cumbersome synthesis strategy.

Multimodal Tracking of Controlled Infections in Mice.

There is a need to develop diagnostic and analytical tools that allow noninvasive monitoring of bacterial growth and dissemination in vivo. For such cell-tracking studies to hold translational value to controlled human infections, in which volunteers are experimentally colonized, they should not require genetic modification, and they should allow tracking over a number of replication cycles. To gauge if an antimicrobial peptide tracer, Tc-UBI-Cy5, which contains both a fluorescent and a radioactive moiety, could be used for such in vivo bacterial tracking, we performed longitudinal imaging of a thigh-muscle infection with Tc-UBI-Cy5-labeled .

Tracers for Fluorescence-Guided Surgery: How Elongation of the Polymethine Chain in Cyanine Dyes Alters the Pharmacokinetics of a Dual-Modality c[RGDyK] Tracer.

The potential of receptor-mediated fluorescence-based image-guided surgery tracers is generally linked to the near-infrared emission profile and good-manufacturing-production availability of fluorescent dyes. Surprisingly, little is known about the critical interaction between the structural composition of the dyes and the pharmacokinetics of the tracers. In this study, a dual-modality tracer design was used to systematically and quantitatively evaluate the influence of elongation of the polymethine chain in a fluorescent cyanine dye on the imaging potential of a targeted tracer.