Production of Lentiviral Particles.

Lentiviral-mediated transfection technique is a powerful tool for gene modification in preclinical studies. By using this technique, the desired gene modification can be achieved easily in immune cells, nondividing and terminally differentiated cells, including hematopoietic stem cells, neurons, and even tumor cells, which other viral vectors cannot do. The main considerations of therapeutic gene delivery using a lentiviral system are the risk of insertional mutagenesis and the immune reaction elicited by infected cells. Although some biosafety concerns need to be addressed before clinical trials in rheumatoid arthritis, the lentiviral system targeting therapeutic targets has been widely used for in vivo gene transfer in animal models. In this chapter, the protocols for production of viral particles and viral concentration are provided.