Lentiviral Vectors: From Wild-Type Viruses to Efficient Multi-Functional Delivery Vectors

Extensive studies about the human immunodeficiency virus type 1 (HIV-1) have allowed the generation of lentiviral vectors as gene delivery vehicles with enhanced safety and efficacy features. In this review, several strategies for controlling the molecular mechanisms occurring during the lentiviral vector manufacturing process are presented. Specifically, modifications focused on LVV manufacturing components, such as plasmids or the producer cell line, that enable increased safety, integrity, and potency of the produced LVV, as well as manufacturing efficiency. Considering the stochasticity of the LVV manufacturing process from plasmid transfection until the budding of the virus from the target cell, minimal modifications might have a huge impact on the final LVV yield. Indeed, the extent of a potential impact may vary depending on the specificities of each LVV regarding the particular genetic payload or the envelope protein. Thus, the feasibility of each of the optimizations described herein requires thorough evaluation. The second part of the review examines the potential multi-purpose nature of the LVV. Growing research in the field has enabled the development of new engineered modalities of LVV, expanding their application scope beyond the traditional ex vivo DNA delivery approach. LVVs are becoming a versatile tool for the packaging or delivery of cargo in the form of DNA, RNA, or protein, allowing their use for in vivo approaches, vaccinology, or gene editing, among others.