Multidimensional control of therapeutic human cell function with synthetic gene circuits

Abstract

Synthetic gene circuits that precisely control human cell function could expand the capabilities of gene- and cell-based therapies. However, platforms for developing circuits in primary human cells that drive robust functional changes in vivo and have compositions suitable for clinical use are lacking. Here, we developed synthetic zinc finger transcription regulators (synZiFTRs), which are compact and based largely on human-derived proteins. As a proof of principle, we engineered gene switches and circuits that allow precise, user-defined control over therapeutically relevant genes in primary T cells using orthogonal, US Food and Drug Administration–approved small-molecule inducers. Our circuits can instruct T cells to sequentially activate multiple cellular programs such as proliferation and antitumor activity to drive synergistic therapeutic responses. This platform should accelerate the development and clinical translation of synthetic gene circuits in diverse human cell types and contexts.

Systems Medicine for Precise Targeting of Glioblastoma

“…The benefit of these gates allows the integration of multiple circuits to process inputs [ 150 ]. A study developed synthetic zinc finger transcription regulators (synZiFTRs), derived from human proteins, and gene switches and circuits which enable T-cells to activate antitumor activity [ 151 ]. Regulation of cellular functions by engineering novel sensors and receptors for intracellular signaling pathways as an approach for treatment has been used for a few diseases [ 152 ].…”

Multi-input drug-controlled switches of mammalian gene expression based on engineered nuclear hormone receptors

“…In addition, an ER variant (ER T2 ) has previously been engineered that displays reduced sensitivity to the endogenous ER ligand 17β-estradiol (E2), but responds to the active tamoxifen metabolite 4-hydroxytamoxifen (4OHT) 31 . Such a variant could be useful for biomedical applications due to its increased orthogonality in a physiological context and has been used in various bioengineering and synthetic biology approaches 18, 27, 31, 46 .…”

“…Thus, our results encourage a systematic characterization of functional dimers on the scale of the entire NHR protein superfamily, which could identify a breadth of new multi-drug-controlled switches that regulate gene outputs from the existing E/GRE response element. Conversely, the use of synthetic DBDs based on engineered zinc-finger domains 18, 48 could allow NHR-based switches to control target expression from new DNA sites and thus enable higher-order complexity via multiplexing.…”

“…For biomedical applications of switches in engineered mammalian cells, clinically approved smallmolecule drugs represent ideal inputs because of their well-characterized pharmacodynamic, pharmacokinetic and safety profiles as well as potential synergistic effects that could be elicited with respect to disease treatment. Several drug-controlled protein switches have been developed that are based on repurposed natural proteins and/or de novo designed proteins 7,8,[14][15][16][17][18][19][20][21][22][23][24][25][26][27] . However, in most of these studies, individual switches responded to a single molecular input at a time.…”

The race to supercharge cancer-fighting T cells

“…Other synthetic circuits have been designed to allow precise regulation of CAR expression, by placing it under the control of genetic elements that activate the necessary genes in response to a drug 8 . So far, however, most of these complicated designs have not yet gone through the safety studies and standardization required for use in people, says Sadelain.…”