Exosome as a Vehicle for Delivery of Membrane Protein Therapeutics, PH20, for Enhanced Tumor Penetration and Antitumor Efficacy

Abstract

As biochemical and functional studies of membrane protein remain a challenge, there is growing interest in the application of nanotechnology to solve the difficulties of developing membrane protein therapeutics. Exosome, composed of lipid bilayer enclosed nanosized extracellular vesicles, is a successful platform for providing a native membrane composition. This study reports an enzymatic exosome, which harbors native PH20 hyaluronidase (Exo-PH20), which is able to penetrate deeply into tumor foci via hyaluronan degradation, allowing tumor growth inhibition and increased T cell infiltration into the tumor. This exosome-based strategy is developed to overcome the immunosuppressive and anticancer therapy-resistant tumor microenvironment, which is characterized by an overly accumulated extracellular matrix. Notably, this engineered exosome with the native glycosylphosphatidylinositol-anchored form of hyaluronidase has a higher enzymatic activity than a truncated form of the recombinant protein. In addition, the exosome-mediated codelivery of PH20 hyaluronidase and a chemotherapeutic (doxorubicin) efficiently inhibits tumor growth. This exosome is designed to degrade hyaluronan, thereby augmenting nanoparticle penetration and drug diffusion. The results thus show that this is a promising exosome-based platform that harbors not only a membrane-associated enzyme with high activity but also therapeutic payloads.

Prospects and challenges of extracellular vesicle-based drug delivery system: considering cell source

“…Haney et al (2015) have developed an EVbased antioxidant and catalase delivery system for the treatment of Parkinson's disease. Hong et al (2018) designed a PH20 hyaluronidase delivery nano-system based on EV, which is able to penetrate deeply into tumor foci via hyaluronan degradation, allowing tumor growth inhibition and increased T cell infiltration. There are many other studies that have shown protein or peptide within exosomes provides an intended purpose to targeted therapy.…”

Extracellular vesicles as a platform for membrane‐associated therapeutic protein delivery

“…Our experiments revealed that the generated exosomes could effectively degrade HA both in vitro and in vivo . Remarkably, PH20 proteins were found to be highly enriched in the lipid raft fraction of these exosomes, and their enzymatic activity was 3-fold higher than that of truncated recombinant proteins [119]. Using the GPI-anchor signal peptide of decay-accelerating factor (DAF), which can be selectively sorted to EVs during reticulocyte maturation, Kooijmans et al further showed that GPI-anchored EGFR nanobodies could effectively bind EGFR-expressing tumour cells under static and flow conditions [99].…”

Development and MPI tracking of novel hypoxia-targeted theranostic exosomes

“…For example, hypoxia-targeting peptides and antibodies could be used to bioengineer the exosomes and enhance their ability to target hypoxic cells in vivo [58,59]. Furthermore, exosomes released from different types of cells, such as cancer cells, immune cells, or stem cells, could be more effective in targeting hypoxic cancer in in vivo [16,60]. Additionally, these in vivo studies could be helpful to understand the role of exosomes as vaccine for cancer immunotherapy [61-63].…”