Transfection

Transfection designates the process of deliberately introducing nucleic acids including plasmid DNA, mRNA, or oligonucleotides into eukaryotic cells, enabling transient or stable gene expression for research, protein production, or therapeutic applications. This fundamental molecular biology technique employs diverse methods including chemical reagents forming complexes with nucleic acids facilitating membrane crossing, physical methods including electroporation creating transient membrane pores, or viral transduction using viral vectors for efficient delivery.

The biopharmaceutical industry extensively employs transfection across research, development, and manufacturing. Transient transfection enables rapid protein production for research, screening, or small-scale material generation without stable cell line development. Manufacturing employs large-scale transient transfection producing recombinant proteins, viral vectors, or vaccines in suspension cultures. Stable transfection creates production cell lines through integration of expression constructs into chromosomes, requiring selection and cloning. Gene therapy development uses transfection producing viral vectors in packaging cell lines. Functional studies employ transfection introducing genes, shRNAs, or CRISPR components investigating gene function or validating targets. Challenges include variability between experiments, cell-type dependence, potential toxicity from reagents, and scale-up difficulties. As demand grows for viral vectors, recombinant proteins, and cellular therapies, transfection methods continue evolving supporting efficient nucleic acid delivery enabling biopharmaceutical innovation.