111In-Labeled Glycoprotein Nonmetastatic b (GPNMB) Targeted Gemini Surfactant-Based Nanoparticles against Melanoma: In Vitro Characterization and in Vivo Evaluation in Melanoma Mouse Xenograft Model

Melanoma is a devastating form of skin cancer with high tendency to metastasis. This work addresses the development of new targeted nanoparticles that can be used for single-photon emission computed tomography (SPECT) imaging of melanoma. Melanoma-specific glycoprotein nonmetastatic b (GPNMB) antigen targeted and nontargeted gemini nanoparticles were prepared, characterized, and radiolabeled with 111In. 111In-labeled nanoparticles were composed of gemini surfactant grafted with monoclonal antibody Fab fragment that targeted GPNMB. Specific uptake of GPNMB-Fab was studied in six melanoma cell lines using flow cytometry. In vitro cellular uptake and internalization were studied using flow cytometry, confocal laser scanning microscopy, and radiometric techniques. Specific uptake of anti-GPNMB targeted nanoparticles was observed in GPNMB expressing cells, which was higher than low expressing or control cells. In vitro studies showed that conjugation of GPNMB targeted nanoparticles led to enhanced intracellula...