Academic research trends continue to drive transfection technology advancements. Researchers hope to use more biologically relevant yet hard-to-transfect cell models in addition to the standard immortalized cell lines, along with a broader range of nucleic acids, such as RNA variants. These possibilities lead to interesting twists that demand innovation.
Efficiency and viability rates, process reproducibility, robustness and reliability, as well as scalability—all these considerations make transfection challenging. A single “best solution” currently does not exist; methodologies satisfy certain experimental parameters, and all come with advantages and disadvantages.
A critical piece of the puzzle for producing new therapies for hard-to-treat diseases, transfection broadly segments into chemically mediated, non-chemically mediated, instrument-based, and viral-vector-based methods, according to Mark Bloomfield, CEO at Polyplus-transfection.
Researchers’ interest in expanding the transfectable repertoire of cell lines and the range of nucleic acids used creates an ongoing need for optimized reagents for specific uses. In parallel, chemically mediated methods have evolved into a sophisticated range of compounds, encompassing lipid- and cationic-based polymer systems, with multiple variants in between.
In addition to research, chemically mediated transfection is used in bioproduction, such as the manufacture of recombinant proteins, antibodies, and viruses, for basic research as well as drug discovery and development applications. The demand for therapeutic proteins as replacements for classical new drug compounds makes the need for additions to the transfection product pipeline even more urgent.
Transient gene expression, when the transfected nucleic acid is not permanently incorporated into the cells’ DNA, is now used broadly in producing larger scales of therapeutic proteins, or new designs of proteins, for further evaluation and study.
Bioproduction applications have sparked requirements for cost containment (via increased cell densities, more efficient transfection rates, higher cell viability, and lower DNA usage), a plethora of enhanced physical growth platforms (in the form of bioreactors and disposable cell culture systems), and a shift toward higher production standards (from research-grade to well-defined GMPs, or good manufacturing practices).
In the vast majority of cases, hard-to-transfect cell lines express very little heparan sulfate proteoglycans on the cell surface (or none in the case of lymphocytes), making it difficult for transfection reagent/nucleic acid complexes to interact with the cell membrane and enter the cell by endocytosis.
Primary cell researchers looking for therapeutic outcomes have pushed transfection reagent manufacturers, such as oligo-chemistry and delivery experts Polyplus-transfection, to develop more efficient, effective, and specialized transfection systems that are optimized for complex therapeutic nucleic acids, designed for systemic delivery in animal models and then in human clinical trials.