PEIpro® product range (PEIpro®, PEIpro®-HQ and PEIpro®-GMP) is the transfection method of choice to achieve reliable viral vector production and high infectious titer yields, with direct scalability and seamless transition from process development up to large-scale clinical-grade manufacturing. PEIpro® product range is composed of three quality grade reagents: R&D grade PEIpro® for process development, higher quality grade PEIpro®-HQ for pre-clinical phase and highest quality grade PEIpro®-GMP for clinical and commercialization phase.
Advanced therapy medicinal products (ATMPs) including Gene Therapy and Cell Therapy have emerged as promising treatments for rare monogenic diseases, immunotherapies (eg. CAR-T) and cancer vaccines. These therapies are based on the delivery of therapeutic nucleic acids to stably alter a cell’s genome. Therapeutic nucleic acids need to be safely delivered into the targeted cells, whether by direct administration (Gene Therapy) or by ex-vivo reengineering of cells that are reinjected into the patient (Cell Therapy). These therapies are based on two main approaches: viral vector and non-viral vector delivery. Both of these methods consist in engineering safe and efficient nanocarriers that contain the desired exogenous nucleic acid for efficient delivery into the targeted cells.
PEIpro®, the gold standard PEI-based transfection reagent for viral vector production
Viral vectors are generally produced in mammalian producer cell lines, typically in HEK-293, HEK-293 derivatives, BHK, VERO cell lines, and growingly into virus-specific packaging cell lines. PEIpro®-based transfection is an effective method that has been used to produced therapeutic viruses such as AAV and lentiviruses (Table 1). For more information on other virus types such as adenoviruses, retroviruses and virus-like particles (VLP), see PEIpro literature.
Table 1. PEIpro®, the gold standard for efficient and reproducible AAV and lentivirus-based viral vector production. List of most recent publications and patents in which PEIpro® was selected as transfection method of choice to produce both AAV and lentiviruses.
Géraldine Guérin-Peyrou, our Marketing and Scientific Support Director, and Senior Scientist Dr. Hanna Leinonen (Kuopio Centre for Gene and Cell Therapy, Finland) were interviewed by BWB TV at Bioprocess International 2018 meeting in Boston. Watch the video to learn more about the benefits of using PEIpro® for viral vector production and on the pioneering work on production of lentivirus and AAV in the iCELLis® Bioreactor using PEIpro (Valkama et al. Gene Ther 2018).
Seamless transition from process development up to clinical trials and commercialization
Already at the Process Development stage, it is essential to assess sourcing of raw materials to facilitate future transition to preclinical and clinical studies. At Polyplus-transfection, we strictly apply the Quality Requirements for the manufacturing of ATMPs with the availability of the same PEIpro® transfection reagent at three quality grades: PEIpro® for initial Process Development, higher quality grade PEIpro®-HQ for pre-clinical and early stage clinical stages, and PEIpro®-GMP for late clinical stage and commercialization. Consequently, large-scale transfection protocols established with PEIpro® during process development are guaranteed to be seamlessly applicable during manufacturing of clinical batches using PEIpro®-HQ and PEIpro®-GMP.
Fig. 1. Reproducible virus titers are achieved with different grades of PEIpro®. Suspension 293-T cells were seeded at 1 x 106 cells/mL in FreeStyle™ F17 medium and transfected with PEIpro®, PEIpro®-HQ and PEIpro®-GMP reagents following the same protocol. AAV were produced with the Helper Free Packaging System (Cell Biolabs) and titers were measured 72h after transfection using a GFP reporter gene expression assay.