Tailored delivery of analgesic ziconotide across a blood brain barrier model using viral nanocontainers

Abstract

The blood brain barrier (BBB) is often an insurmountable obstacle for a large number of candidate drugs, including peptides, antibiotics, and chemotherapeutic agents. Devising an adroit delivery method to cross the BBB is essential to unlocking widespread application of peptide therapeutics. Presented here is an engineered nanocontainer for delivering peptidic drugs across the BBB encapsulating the analgesic marine snail peptide ziconotide (Prialt®). We developed a bi-functional viral nanocontainer based on the Salmonella typhimurium bacteriophage P22 capsid, genetically incorporating ziconotide in the interior cavity, and chemically attaching cell penetrating HIV-Tat peptide on the exterior of the capsid. Virus like particles (VLPs) of P22 containing ziconotide were successfully transported in several BBB models of rat and human brain microvascular endothelial cells (BMVEC) using a recyclable noncytotoxic endocytic pathway. This work demonstrates proof in principle for developing a possible alternative to intrathecal injection of ziconotide using a tunable VLP drug delivery nanocontainer to cross the BBB.

Encapsulin carrier proteins for enhanced expression of antimicrobial peptides

“…To express HBCM2 within the interior lumen of an encapsulin cage, we directly fused the peptide to the N‐terminus of the Enc monomer, which is luminal‐facing based on the X‐ray crystal structure of the encapsulin cage (Sutter et al, ; Figure a,b). Direct fusion also ensures that each peptide is associated with Enc monomer to maximize loading into cages, a strategy that has been successfully employed in other compartmentalization systems (Anand, O'Neil, Lin, Douglas, & Holford, ; Ferlez, Sutter, & Kerfeld, ). To enable release of HBCM2 following purification of the fusion protein, TEV protease recognition sites were placed between the peptide and the Enc monomer as well as at surface accessible locations within Enc to encourage cage disassembly (Figure c).…”

“…Direct fusion also ensures that each peptide is associated with Enc monomer to maximize loading into cages, a strategy that has been successfully employed in other compartmentalization systems (Anand, O'Neil, Lin, Douglas, & Holford, 2015;Ferlez, Sutter, & Kerfeld, 2019). To enable release of HBCM2 following purification of the fusion protein, TEV protease recognition sites were placed between the peptide and the Enc monomer as well as at surface accessible locations within Enc to encourage cage disassembly ( Figure 1c).…”

In vitro screening of nanomedicines through the blood brain barrier: A critical review

“…Noteworthy, for the sake of high-throughput screening, static cell-based models were the most broadly used (only one dynamic model has been reported [323]), although additional strategies are often applied to overcome leakiness of Transwell® monocultures. The tendency towards the use of these models is likely to rise further in the CNS drug discovery field.…”

“…In broad terms, qualitative results from both studies are consistent with each other, which demonstrate that cell-based models might be useful as preliminary screening tools to triage promising nanomedicines. [323] *: these references have calculated apparent permeability values expressed in cm/s; # : these references have conducted in vivo studies to further evidence the brain delivery, BBB: blood brain barrier; CPT-cAMP: 8-(4-chlorophenylthio) adenosine 3′,5′-cyclic monophosphate; RO-20-1724: 4-(3-butoxy-4 methoxybenzyl)-2-imidazolidinone; PECAM: platelet-endothelial cell adhesion molecule.…”

Phage‐Enabled Nanomedicine: From Probes to Therapeutics in Precision Medicine

“…One such example involved the development of a bifunctional viral nanocontainer utilizing the Salmonella typhimurium phage P22 capsid. [142] The capsid was genetically engineered to incorporate ziconotide in the interior cavity. Next, HIV Tat peptide was chemically attached to the exterior of the capsid for better cell penetration.…”