Development of an Engineered Single-Domain Antibody for Targeting MET in Non-Small Cell Lung Cancer

• Published in: Bioconjugate chemistry Vol. 35; no. 3; pp. 389 - 399
• Main Authors: Luo, Natalie Y., Minne, Rachel L., Gallant, Joseph P., Gunaratne, Gihan S., West, Jayden L., Javeri, Saahil, Robertson, Austin J., Lake, Eric W., Engle, Jonathan W., Mixdorf, Jason C., Aluicio-Sarduy, Eduardo, Nickel, Kwang P., Hernandez, Reinier, Kimple, Randall J., Baschnagel, Andrew M., LeBeau, Aaron M.
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 20.03.2024
• Subjects: Affinity; Antibodies; c-Met protein; Camelids; Computed tomography; Fc receptors; Flow cytometry; Fusion protein; Immunofluorescence; In vivo methods and tests; Kinases; Localization; Lung cancer; Medical imaging; Non-small cell lung carcinoma; Payloads; Phage display; Positron emission; Protein-tyrosine kinase receptors; Small cell lung carcinoma; Tyrosine; Xenotransplantation; Zirconium isotopes
• ISSN: 1043-1802; 1520-4812
• DOI: 10.1021/acs.bioconjchem.4c00019

The Mesenchymal Epithelial Transition (MET) receptor tyrosine kinase is upregulated or mutated in 5% of non-small-cell lung cancer (NSCLC) patients and overexpressed in multiple other cancers. We sought to develop a novel single-domain camelid antibody with high affinity for MET that could be used to deliver conjugated payloads to MET expressing cancers. From a naïve camelid variable-heavy-heavy (VHH) domain phage display library, we identified a VHH clone termed 1E7 that displayed high affinity for human MET and was cross-reactive with MET across multiple species. When expressed as a bivalent human Fc fusion protein, 1E7-Fc was found to selectively bind to EBC-1 (MET amplified) and UW-Lung 21 (MET exon 14 mutated) cell lines by flow cytometry and immunofluorescence imaging. Next, we investigated the ability of [89Zr]­Zr-1E7-Fc to detect MET expression in vivo by PET/CT imaging. [89Zr]­Zr-1E7-Fc demonstrated rapid localization and high tumor uptake in both xenografts with a %ID/g of 6.4 and 5.8 for EBC-1 and UW-Lung 21 at 24 h, respectively. At the 24 h time point, clearance from secondary and nontarget tissues was also observed. Altogether, our data suggest that 1E7-Fc represents a platform technology that can be employed to potentially both image and treat MET-altered NSCLC.