Black Phosphorus Nanosheets Assist Nanoerythrosomes for Efficient mRNA Vaccine Delivery and Immune Activation

Abstract

Messenger RNA (mRNA)‐based vaccines have enormous potential in infectious disease prevention and tumor neoantigen application. However, developing an advanced delivery system for efficient mRNA delivery and intracellular release for protein translation remains a challenge. Herein, a biocompatible biomimetic system is designed using red blood cell‐derived nanoerythrosomes (NER) and black phosphorus nanosheets (BP) for mRNA delivery. BP is covalently modified with polyethyleneimine (PEI), serving as a core to efficiently condense mRNA via electrostatic interactions. To facilitate the spleen targeting of the mRNA‐loaded BP (BPmRNA), NER is co‐extruded with BPmRNA to construct a stable “core–shell” nanovaccine (NER@BPmRNA). The mRNA nanovaccine exhibits efficient protein expression and immune activation via BP‐mediated adjuvant effect and enhanced lysosomal escape. In vivo evaluation demonstrates that the system delivery of mRNA encoding coronavirus receptor‐binding domain (RBD) significantly increases the antibody titer and pseudovirus neutralization effect compared with that of NER without BP assistance. Furthermore, the mRNA extracted from mouse melanoma tissues is utilized to simulate tumor neoantigen delivered by NER@BPmRNA. In the vaccinated mice, BP‐assisted NER for the delivery of melanoma mRNA can induce more antibodies that specifically recognize tumor antigens. Thus, BP‐assisted NER can serve as a safe and effective delivery vehicle in mRNA‐based therapy.

Nanomaterial Delivery Vehicles for the Development of Neoantigen Tumor Vaccines for Personalized Treatment

“…To solve the problem of easy degradation and expression of RNA, RNA structure can be modified, such as through codon optimization [41], nucleotide modification [42], appropriate modification of structural elements (UTR's, 5 ′ capping, ORF, Poly(A) tail) [43], or piggybacking with liposomes [44], nanosheets [45], and so on.…”

Delivery of nucleic acids using nanomaterials

“…BP was covalently modified with PEI and served as the core to efficiently condense mRNA via electrostatic interactions, forming NER@BPmRNA. In in vivo experiments, they demonstrated that NER@BP, when injected into the muscle, effectively targeted the spleen for antigen delivery [ 162 ].…”

A black phosphorus nanosheet-based RNA delivery system for prostate cancer therapy by increasing the expression level of tumor suppressor gene PTEN via CeRNA mechanism

“…Compared with other nanomaterials, black phosphorus nanosheets (BP) have a higher surface-to-volume ratio due to the wrinkled lattice configuration, which could increase the drug loading capacity [ 10 ]. For instance, Yang et al [ 11 ] designed a biocompatible biomimetic system for mRNA delivery using red blood-cell-derived nanoerythrocytes (NER) and BP, and the results showed that systematic delivery of coronavirus receptor-binding domain (RBD) mRNA significantly improved antibody titers and pseudovirus neutralization compared with NER without BP assistance. Therefore, BP could be used as a safe and effective delivery tool for RNA-based therapies.…”

“…Therefore, BP could be used as a safe and effective delivery tool for RNA-based therapies. However, BP itself was also reported to be easily oxidized and degraded to nitrite ions and phosphate and naked BP with negative charge cannot efficiently load and deliver RNA [ 6 , 11 ], which could be avoided by PEI modification since PEI is positively charged and could accomplish lysosomal escape through the “proton sponge effect” [ 12 ]. For example, Wang et al used a survivin siRNA delivery system based on PEI-functionalized BP nanosheets to effectively inhibit tumor growth by silencing survivin expression [ 13 ].…”