<p>Despite recent breakthroughs in cancer immunotherapy, solid tumors continue to evade treatment due to their immunosuppressive microenvironment. Gene therapy can make such “cold” tumors “hot”, initiate therapeutic chain reactions, repair cancer-specific genetic mutations, or solve cell pathologies; however, it lacks the specific delivery vehicle for tumors or genetic diseases. Here, I explore a T cell line as platform for lentiviral production and delivery. I show that Jurkat cells can produce functional lentivirus, successfully transferring a fluorescence reporter gene locally to cancer cells under controlled in vitro conditions and allowing quantification of efficiency. Furthermore, a Tet-On inducible promoter could precisely and timely regulate lentivirus production. The comprehensive lentiviral T cell system is anticipated to safely provide specific, efficient, and stable gene expression in vivo to any tissue in the future, with effortless adaptation.</p>