Phage Particles of Controlled Length and Genome for In Vivo Targeted Glioblastoma Imaging and Therapeutic Delivery

Abstract

M13 bacteriophage (phage) are versatile, genetically tunable nanocarriers that have been recently adapted for use as diagnostic and therapeutic platforms. Applying p3 capsid chlorotoxin fusion with the “inho” circular single-stranded DNA (cssDNA) gene packaging system, we produced miniature chlorotoxin inho (CTX-inho) phage particles with a minimum length of 50 nm that can target intracranial orthotopic patient-derived GBM22 glioblastoma tumors in the brains of mice. Systemically administered indocyanine green conjugated CTX-inho phage accumulated in brain tumors, facilitating shortwave 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 delivery platform.

Forging the Frontiers of Image-Guided Neurosurgery—The Emerging Uses of Theranostics in Neurosurgical Oncology

“…Our preliminary data demonstrating the ability of IR1050-CTX-M13 ϕ and SWCNT-CTX-M13 ϕ to detect patient-derived GBM22 tumors in the brains of mice using SWIR imaging ( Figures 1A,B , right panel, Ex vivo SWIR images), and our previously published studies using NIR II conjugated-M13 ϕ expressing tumor-targeting peptides to detect ovarian cancer tumors during real-time surgical resection in a mouse model of ovarian cancer ( Yi et al, 2012 ; Ghosh et al, 2014 ), further enforces the potential of using M13 ϕ as a versatile theranostic platform for use in FGS and multimodal treatment of a wide range of tumors, including brain tumors. We are currently conducting further preclinical studies to better characterize the pharmacokinetics, pharmacodynamics, and safety of M13 ϕ in the CNS to assess the translational potential for use in human trials ( Tsedev et al, 2022 ).…”

M13 phage: a versatile building block for a highly specific analysis platform

“…Major capsid protein pVIII consists of about 2700 copies, which accounts for 98% of the whole mass of M13 phage and contains 50 amino acids (AA). Each pVIII is composed of three domains: positively charged domain (40-50 AA) that interacts electrostatically with phage genomic DNA, intermediate hydrophobic domain (21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38)(39), and the N-terminal domain (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20). A total of 2700 copies of pVIII protein are helically wrapped around phage DNA through electrostatic interaction between phage genomic DNA and the positively charged domain of pVIII protein, leaving the M13 surface with negative charge.…”

“…This advantage not only facilitates the convenient fabrication of phage display libraries, especially phage display antibody libraries [20], but also promoted large-scale production of ssDNA [18], for instance, DNA origami. In addition, by altering the size of the phagemid, the length of M13 nanofibers can be finely tuned from 50 to 1300 nm, which was used for constructing stiffness-tunable nanofoams and ultra-small M13 for in vivo targeted glioblastoma imaging and therapy [21,22]. Although phagemid display system achieved success in constructing phage display libraries, it may not be the perfect choice for fabricating M13-based functional materials due to the low yield of recombinant M13.…”

Micro‐Nanocarriers Based Drug Delivery Technology for Blood‐Brain Barrier Crossing and Brain Tumor Targeting Therapy

“…[ 235 ] Filamentous phages also have an engineered nature, a rod‐like structure that tends to migrate along the vessel wall more than spherical nanoparticles, cellular uptake, and transport allowed by a high aspect ratio, making them good nanoparticle carriers for targeting CNS across BBB transport. [ 236 ] Bacteriophage targeting approaches can be divided into two main categories: passive and active targeting. In passive targeting, NPs evade the immune system through their small size and accumulate in tissues through a leaky vascular system at inflammatory and tumor sites; active targeting uses surface ligands to mediate recognition of specific molecules with motifs expressed on target cells or tissues, improving drug accumulation and cellular uptake and thus reducing side effects.…”

“…In passive targeting, NPs evade the immune system through their small size and accumulate in tissues through a leaky vascular system at inflammatory and tumor sites; active targeting uses surface ligands to mediate recognition of specific molecules with motifs expressed on target cells or tissues, improving drug accumulation and cellular uptake and thus reducing side effects. [236] Loi et al found that in preclinical mouse models carrying human neuroblastoma, selection of the corresponding targeting peptide ligands by in vitro/ex vivo phage combinations and coupling with DOX-loaded liposomes resulted in significant suppression of tumor volume and improved survival. [237]…”