Lentivirus-Like Particles (LVLPs)

Overview of LVLPs

VLPs that carry RNP payloads take benefit of viral delivery's efficiency and tissue targeting while avoiding the dangers associated with viral genome integration and long-term editing agent expression. Lentiviruses are a popular scaffold for VLP packaging due to their flexible structure and large particle size, which can accommodate non-natural protein cargo, and their tropism can be modified by pseudotyping virions with various envelope glycoproteins. Therefore, lentivirus-enveloped VLP (LVLP), can target specific cells. LVLPs are widely used to deliver gene editors to avoid the long-term expression of nucleases mediated by lentiviral vectors will increase the off-target effects of gene editing, to achieve the transient expression of gene editing proteins. Creative Biolabs developed two main strategies for LVLP packaging of mRNA:

• LVLP packages mRNA by interacting with the Ψ packing signal at the lentiviral RNA LTR and the nucleocapsid protein, preventing reverse transcriptase and integrase from becoming active. The mRNA cannot be reverse transcribed and can only serve as a template for translation.
• RNA aptamers engage with aptamer-binding proteins to package and deliver mRNA without LTRs, avoiding reverse transcription and integration. This mRNA is then successfully translated into target cells to perform its purpose.

Application of LVLPs

LVLPs are commonly employed in gene editing because of their ability to dramatically reduce off-target and immunogenicity. Figure 1 depicts the development of a new mRNA delivery technique based on a lentiviral system. This technique uses RNA aptamers and aptamer-binding proteins for LVLP packaging of mRNA that encodes one of the longest Cas9 proteins (SpCas9) and vascular endothelial growth factor A, Vegfa's sgRNA, to treat disorders caused by Vegfa-induced wet age-related macular degeneration. After subretinal injections in mice, LVLP-CRISPR effectively edits 44% of the Vegfa gene in the retinal pigment epithelium cell and reduces 63% of new blood vessels. In addition, The Cas9 mRNA delivered lasts only 72 hours, reducing the risk of off-target and immune responses. This highlights the potential of LVLP delivery vectors for safe and effective gene editing technology.

Fig.1 The packaging process of LVLP for co-delivery of Cas9 mRNA and sgRNA.¹

SERVICES

Creative Biolabs is committed to offering LVLP services for worldwide customers. Our services encompass custom plan development tailored to customer specifications and LVLP attributes, lentiviral vector manufacturing, VLP assembly and purification, protein expression assessment, and more. For comprehensive details, please reach out to us. We are committed to providing the most suitable service for your project needs.

Reference

1. Ling, Sikai, et al. "Lentiviral delivery of co-packaged Cas9 mRNA and a Vegfa-targeting guide RNA prevents wet age-related macular degeneration in mice."Nature Biomedical Engineering 5.2 (2021): 144-156.