A Lenalidomide-Inducible Suicide Switch for Gene- and Cell-Based Therapy
- 1Krantz Family Center for Cancer Research, Massachusetts General Hospital, Boston, MA 02114, USA
Abstract
Genetically modified immune effector cells, including chimeric antigen receptor (CAR) T cells, have emerged as transformative anti-cancer agents. However, these autonomous, living therapies are limited by difficult-to-control hyperactivation toxicities. To achieve their full potential as therapies for a broader range of diseases, CAR T cells must target novel antigens and integrate further potency enhancements that raise the possibility of novel and intensified toxicities. High performance safety systems are needed to restrain these highly active next-generation gene- and cell-based therapies. Cell therapy suicide switches remain infrequently used, and are currently limited by inaccessible controller drugs, incomplete cell depletion, fitness cost, and immunogenicity. To address these issues, we engineered a fully human sequence-based cell therapy suicide switch based on the overexpression of Caspase-Activated DNase (CAD) and its stoichiometric chaperone/inhibitor ICAD fused to a lenalidomide-inducible degron. Acute destabilization of ICAD with the broadly available, off-patent molecular glue degrader drug lenalidomide uncaged CAD to induce DNA damage and cell death. By this degradable cage mechanism, the ICAD-CAD suicide switch achieved long-term expression in primary human T cells without detectable leakiness, and deep drug-induced cell depletion. The ICAD-CAD switch was generalizable to alternative acute destabilization systems. Genome-wide CRISPR screening established the necessity of CAD and the lenalidomide-interacting E3 ubiquitin ligase substrate adaptor CRBN for switch function. When co-delivered with a CAR, ICAD-CAD CAR T cells retained effector functions and could be rapidly depleted with lenalidomide.
Related
- An inducible human LDLR transgenic mouse model for enhanced lentiviral gene delivery to murine immune cells
- A tetracycline-inducible promoter for gene expression in Gram-negative bacteria including Acinetobacter baumannii
- Engineering and characterisation of AAVS1 FRT cell lines for inducible and dose-dependent gene expression
- Theophylline-dependent synthetic riboswitches enable tightly regulated inducible gene expression in tobacco plastids
- An epigenetic candidate–gene association study of parental styles in suicide attempters with substance use disorders
BibTeX
@misc{sarkar2026lenalidomideinducible,
title = {{A Lenalidomide-Inducible Suicide Switch for Gene- and Cell-Based Therapy}},
author = {D. Sarkar and W. Lin and N. H. Knudsen and J. Evans and J. Kim and S. M. Coscia and I. C. Lane and A. Cheng and N. Radde and M. Talla and A. Pham and T. Kienka and E. Schneider and G. Kembuan and M. Slabicki and V. Koduri and A. Sperling and M. V. Maus and R. T. Manguso and M. Jan},
howpublished = {bioRxiv},
year = {2026},
month = sep,
doi = {10.64898/2026.09.30.755642},
url = {https://www.biorxiv.org/content/10.64898/2026.09.30.755642v1},
note = {CC BY-NC-ND},
}
RIS
TY - UNPB
TI - A Lenalidomide-Inducible Suicide Switch for Gene- and Cell-Based Therapy
AU - D. Sarkar
AU - W. Lin
AU - N. H. Knudsen
AU - J. Evans
AU - J. Kim
AU - S. M. Coscia
AU - I. C. Lane
AU - A. Cheng
AU - N. Radde
AU - M. Talla
AU - A. Pham
AU - T. Kienka
AU - E. Schneider
AU - G. Kembuan
AU - M. Slabicki
AU - V. Koduri
AU - A. Sperling
AU - M. V. Maus
AU - R. T. Manguso
AU - M. Jan
PY - 2026
DA - 2026/09/30
PB - bioRxiv
DO - 10.64898/2026.09.30.755642
UR - https://www.biorxiv.org/content/10.64898/2026.09.30.755642v1
AB - Genetically modified immune effector cells, including chimeric antigen receptor (CAR) T cells, have emerged as transformative anti-cancer agents. However, these autonomous, living therapies are limited by difficult-to-control hyperactivation toxicities. To achieve their full potential as therapies for a broader range of diseases, CAR T cells must target novel antigens and integrate further potency enhancements that raise the possibility of novel and intensified toxicities. High performance safety systems are needed to restrain these highly active next-generation gene- and cell-based therapies. Cell therapy suicide switches remain infrequently used, and are currently limited by inaccessible controller drugs, incomplete cell depletion, fitness cost, and immunogenicity. To address these issues, we engineered a fully human sequence-based cell therapy suicide switch based on the overexpression of Caspase-Activated DNase (CAD) and its stoichiometric chaperone/inhibitor ICAD fused to a lenalidomide-inducible degron. Acute destabilization of ICAD with the broadly available, off-patent molecular glue degrader drug lenalidomide uncaged CAD to induce DNA damage and cell death. By this degradable cage mechanism, the ICAD-CAD suicide switch achieved long-term expression in primary human T cells without detectable leakiness, and deep drug-induced cell depletion. The ICAD-CAD switch was generalizable to alternative acute destabilization systems. Genome-wide CRISPR screening established the necessity of CAD and the lenalidomide-interacting E3 ubiquitin ligase substrate adaptor CRBN for switch function. When co-delivered with a CAR, ICAD-CAD CAR T cells retained effector functions and could be rapidly depleted with lenalidomide.
ER -