EXTH-24. FILAMENTOUS PHAGE AS A NANOTHERANOSTIC FOR THE DETECTION, IMAGING, AND TREATMENT OF GLIOMAS

Abstract

Abstract Current standard of care treatment for gliomas includes maximal safe surgical resection followed by concurrent chemoradiation, however, the diffuse infiltrative nature of gliomas present certain challenges for neurosurgeons to clearly visualize tumor tissue under conventional white light during microsurgical resection. Fluorescence-guided surgical techniques have been recently introduced to help surgeons better visualize tumor tissue under the operating microscope. Fluorescent dyes conjugated to nanoscale materials that are functionalized with glioma-targeting peptide sequences, such as the 39 amino acid chlorotoxin (CTX) peptide sequence, have demonstrated clinical efficacy in recognizing microscopic tumor cells during surgeries. M13 bacteriophage (phage) are versatile, genetically tunable nanocarriers that have been recently adapted for use as theranostic platforms. Applying p3 capsid CTX fusion with a unique “inho” circular single-stranded DNA (cssDNA) gene packaging system, we produced miniature CTX inho (CTX-inho phage particles with a minimum length of 50 nm that can target intracranial orthotopic patient-derived glioblastoma tumors in the brains of mice. Systemically-administered indocyanine green-conjugated CTX-inho phage accumulated in brain tumors, facilitating short-wave infrared detection. Furthermore, we show that our inho phage can carry cssDNA that are transcriptionally active when delivered to GBM22 glioma cells in vitro. The ability to modulate the capsid display, surface loading, phage length, and cssDNA gene content makes the recombinant M13 phage particle an ideal nanotheranostic platform for neuro-oncological applications.