Lentiviral vectors: from research to gene therapy

Boro Dropulic, Founder and CEO of Lentigen Corporation, about highly efficient and stable gene delivery offered by Lentiviral vectors.

Lentiviral vectors have broad applications, some of which are:

• Rapid development of cell lines that conditionally express reporters for drug discovery
• Target validation by creating cell lines devoid of specific target proteins
• RNAi expressing primary cells and cell lines – for the stable knockdown of gene expression
• Rapid master cell line development for optimised protein manufacture
• Rapid and cost effective method to manufacture vaccines from mammalian cells
• Efficient generation of transgenic animals and other animal models
• Gene therapy

Lentiviral Vectors are viral-based gene delivery systems that can stably deliver genes or RNAi into primary cells or cell lines with up to 100 percent efficiency. Gene delivery is stable because the target gene or gene silencing sequence is integrated in the chromosome and is copied along with the DNA of the cell every time the cell divides. One of the defining features of LVs is their ability to integrate into non-dividing cells, in contrast to other vectors that either do not integrate efficiently into chromosomal DNA (e.g. non-viral, adenoviral and adenoviral-associated vectors) or can only integrate upon cell division (e.g. conventional retroviral vectors). Lentigen has developed a unique Lentiviral vector system that has advantages over other systems.

The advantages Lentigen’s LentiMax technology offers over other Lentiviral vector systems include:

• A high through-put modular LV system that allows for the customisation of gene and reporter, insertion of other elements, and choice of envelope pseudotype
• Robust production methods with stringent quality control (batch records, SOPs etc.)
• High functional titers in the range of 1x108-1x109 per ml
• Clinical translatability – the vectors used for R&D are designed for a wide variety of future applications, including gene therapy
• Scalable manufacturing process – LentiMax can be manufactured at scales from less than 100ul to multiple liter quantities of final concentrated and purified product
• Availability of full release testing of final GMP Lentiviral vector product
• Unique intellectual property that permits commercialization of products by Lentigen’s partners

Clinical Applications
Vaccine Manufacturing
Lentigen has developed a virus-like particle (VLP) vaccine technology (LentiVLP technology) for the rapid and precise production of vaccines, such as pandemic and seasonal influenza. Lentigen has manufactured LVs that produce VLPs that comprise a core protein and various specific hemagglutinin (H) and neuraminidase (N) surface antigens of influenza. The same approach could be used for other infectious diseases.

Biogenerics
Lentigen and its partners are able to use its core technology to rapidly produce a broad array of biogeneric proteins and proprietary products, such as monoclonal antibodies. As LentiMax Lentiviral vectors insert their genetic material in areas of open chromatin (areas that are consistently expressed), proteins produced by cell lines transduced with lentiviral vectors are likely to exhibit high levels of protein production. The result is more efficient production of therapeutic proteins, such as monoclonal antibodies, with higher yields, faster development times and decreased manufacturing costs.
The key advantages of using LentiMax for protein manufacturing are as follows:

• Rapid development of master cell lines for protein manufacturing
• High protein production due to instantaneous multiple integration events
• No selection required to generate high copy number cell lines
• Rapid transition from high throughput protein screening to master cell line
• Mammalian cell glycosylation of produced proteins

Gene Therapy
Lentigen’s LentiMax system has been developed with clinical translation in mind. Lentigen has numerous gene therapy collaborations in oncology, genetic disease, cardiovascular, infectious diseases and regenerative medicine. Our manufacturing process allows for large scale GLP and GMP vector manufacturing at an affordable cost. We provide our collaborators with research and GLP grade Lentiviral vector material, which are used for pre-clinical validation studies to support IND submission. Lentigen will then manufacture GMP Lentiviral vector material for the clinical trials. We also assist our collaborators through the regulatory process when required. Lentigen can act as a contractor, providing vector manufacturing support, or collaborate from early proof-of-concept stages through to commercialisation. LentiMax is developed with unique intellectual property that provides Lentigen’s partners the freedom to commercialise products developed or derived from LentiMax.

BIO
Dr. Boro Dropulic is the Founder of Lentigen and serves as its Chief Executive Officer. He is one of the leading experts in Lentiviral Vector technology. Prior to founding Lentigen, he was Founder and Chief Scientific Officer of VIRxSYS, where he successfully led a multidisciplinary team to initiate and complete the first ever Lentiviral Vector clinical trial in humans. Prior to founding VIRxSYS, Dropulic was an Instructor and then Adjunct Assistant Professor at Johns Hopkins University School of Medicine, where he was the first to develop a HIV-based vector targeted to inhibit the replication of the HIV/AIDS virus.