Intracellular paired agent imaging enables improved evaluation of tyrosine kinase inhibitor target engagement.

Targeting the aberrant epidermal growth factor receptor (EGFR) signaling pathway is an attractive choice for many cancers (e.g., non-small cell lung carcinoma (NSCLC) and head and neck squamous cell carcinoma (HNSCC)).

Simultaneous extracellular and intracellular quantification of EGFR using paired-agent imaging in an tumor model.

Quantification of protein concentrations is often a static and tissue destructive technique. Paired-agent imaging (PAI) using matched targeted and untargeted agents has been established as a dynamic method for quantifying the extracellular domain of epidermal growth factor receptor (EGFR) in a variety of tumor lines. Here we extend the PAI model to simultaneously quantify the extracellular and intracellular regions of EGFR using novel cell membrane permeable fluorescent small molecules, TRITC-erlotinib (targeted) and BODIPY-N-erlotinib (non-binding control isoform) synthesized in house.

Nile Red derivatives enable improved ratiometric imaging for nerve-specific contrast.

Surgical nerve damage due to difficulty with identification remains a major risk for postsurgical complications and decreased quality of life. Fluorescence-guided surgery offers a means to specifically highlight tissues of interest such as nerves and a number of fluorescence-guided surgical systems are in clinical trial or are approved for clinical use. However, no clinically approved nerve-specific fluorophores exist.