PT  - JOURNAL ARTICLE
AU  - Jan, Max
AU  - Scarfò, Irene
AU  - Larson, Rebecca C.
AU  - Walker, Amanda
AU  - Schmidts, Andrea
AU  - Guirguis, Andrew A.
AU  - Gasser, Jessica A.
AU  - Słabicki, Mikołaj
AU  - Bouffard, Amanda A.
AU  - Castano, Ana P.
AU  - Kann, Michael C.
AU  - Cabral, Maria L.
AU  - Tepper, Alexander
AU  - Grinshpun, Daniel E.
AU  - Sperling, Adam S.
AU  - Kyung, Taeyoon
AU  - Sievers, Quinlan L.
AU  - Birnbaum, Michael E.
AU  - Maus, Marcela V.
AU  - Ebert, Benjamin L.
TI  - Reversible ON- and OFF-switch chimeric antigen receptors controlled by lenalidomide
AID  - 10.1126/scitranslmed.abb6295
DP  - 2021 Jan 06
TA  - Science Translational Medicine
PG  - eabb6295
VI  - 13
IP  - 575
4099  - http://stm.sciencemag.org/content/13/575/eabb6295.short
4100  - http://stm.sciencemag.org/content/13/575/eabb6295.full
AB  - Cell-based treatments such as chimeric antigen receptor (CAR) T cells have been finding increasing applications against cancer and other disorders. However, these treatments can have side effects, and it is difficult to stop the activity of an overactive cell-based therapy once it is inside a patient. To improve regulation of CAR T cell treatment, Jan et al. developed a switch-based system for activating and inactivating these cells. T cells with an OFF switch were deactivated using the drug lenalidomide, whereas those with an ON switch required both lenalidomide and a target antigen for activation, allowing control over the timing of T cell activation.Cell-based therapies are emerging as effective agents against cancer and other diseases. As autonomous “living drugs,” these therapies lack precise control. Chimeric antigen receptor (CAR) T cells effectively target hematologic malignancies but can proliferate rapidly and cause toxicity. We developed ON and OFF switches for CAR T cells using the clinically approved drug lenalidomide, which mediates the proteasomal degradation of several target proteins by inducing interactions between the CRL4CRBN E3 ubiquitin ligase and a C2H2 zinc finger degron motif. We performed a systematic screen to identify “super-degron” tags with enhanced sensitivity to lenalidomide-induced degradation and used these degradable tags to generate OFF-switch degradable CARs. To create an ON switch, we engineered a lenalidomide-inducible dimerization system and developed split CARs that required both lenalidomide and target antigen for activation. Subtherapeutic lenalidomide concentrations controlled the effector functions of ON- and OFF-switch CAR T cells. In vivo, ON-switch split CARs demonstrated lenalidomide-dependent antitumor activity, and OFF-switch degradable CARs were depleted by drug treatment to limit inflammatory cytokine production while retaining antitumor efficacy. Together, the data showed that these lenalidomide-gated switches are rapid, reversible, and clinically suitable systems to control transgene function in diverse gene- and cell-based therapies.