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Biology subjects

Tonai, Y.

Publications and source records attributed to Tonai, Y..

4 recordsLinked to original sources

Programming Targeted Immune Cell Migration Using Orthogonal Chemokine-Receptor Pairs

Chemokines orchestrate the migration of immune cells throughout the body, but harnessing chemokine signaling to engineer targeted cell trafficking is challenging because of their overlapping interactions and broad expression patterns. Here we used structure-guided protein design to engineer orthogonal chemokine-receptor pairs with minimal crosstalk to native systems. T cells engineered with an ortho-receptor selectively infiltrated tissues producing the ortho-chemokine, in vitro and in vivo. By engineering T cells that both sense and secrete the ortho-chemokine, we generated collective swarming behavior in which pioneer cells attract follower cells via an ortho-chemokine gradient self-organized by positive feedback. By providing orthogonal genetic control over both the generation and sensing of chemokine gradients, this system enables the construction of autonomous spatial targeting programs in engineered cells.

synthetic biology↗

Engineering lung-sensing T cells using synthetic receptors targeting RAGE

Our goal was to leverage synthetic biology approaches to engineer lung-sensing T cells that trigger synthetic transcriptional programs only when in the lung. First, we identified a lung-specific cell surface protein, receptor for advanced glycation endproducts (RAGE), expressed at high levels exclusively in the lung. Then, we engineered chimeric antigen receptors (CAR) and synthetic notch receptors (SynNotch) to bind this protein. We showed that anti-RAGE CAR-T cells traffic to and proliferate in the lung exclusively. Anti-RAGE SynNotch receptors activate transcription of a fluorescent reporter only when co-cultured with RAGE+ cell lines or primary lung cells. Finally, we tested an anti-RAGE SynNotch to anti-CD19 CAR circuit in vivo in mice implanted with lung and flank tumors and found that this approach cleared CD19-expressing lung tumors without affecting CD19-expressing flank tumors. Thus, we demonstrate that RAGE is a lung-specific target and that T cells expressing anti-RAGE receptors can sense and activate lung-specific therapeutic transcriptional programs. This approach could be extended to allow cell-based therapies that target and deliver genetically encoded payloads to treat lung diseases while avoiding systemic toxicity.

synthetic biology↗

Exploring the rules of chimeric antigen receptor phenotypic output using combinatorial signaling motif libraries and machine learning

Chimeric antigen receptor (CAR) costimulatory domains steer the phenotypic output of therapeutic T cells. In most cases these domains are derived from native immune receptors, composed of signaling motif combinations selected by evolution. To explore if non-natural combinations of signaling motifs could drive novel cell fates of interest, we constructed a library of CARs containing [~]2,300 synthetic costimulatory domains, built from combinations of 13 peptide signaling motifs. The library produced CARs driving diverse fate outputs, which were sensitive to motif combinations and configurations. Neural networks trained to decode the combinatorial grammar of CAR signaling motifs allowed extraction of key design rules. For example, the non-native combination of TRAF- and PLC{gamma}1-binding motifs was found to simultaneously enhance cytotoxicity and stemness, a clinically desirable phenotype associated with effective and durable tumor killing. The neural network accurately predicts that addition of PLC{gamma}1-binding motifs improves this phenotype when combined with TRAF-binding motifs, but not when combined with other immune signaling motifs (e.g. PI3K-or Grb2-binding motifs). This work shows how libraries built from the minimal building blocks of signaling, combined with machine learning, can efficiently guide engineering of receptors with desired phenotypes. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=60 SRC="FIGDIR/small/474985v2_ufig1.gif" ALT="Figure 1"> View larger version (17K): org.highwire.dtl.DTLVardef@8dbf97org.highwire.dtl.DTLVardef@1d8300org.highwire.dtl.DTLVardef@1838ba0org.highwire.dtl.DTLVardef@143d907_HPS_FORMAT_FIGEXP M_FIG C_FIG

synthetic biology↗

T cell circuits that sense antigen density with an ultrasensitive threshold

Overexpressed tumor associated antigens (e.g. HER2 and EGFR) are attractive targets for therapeutic T cells, but toxic cross-reaction with normal tissues expressing low antigen levels has been observed with Chimeric Antigen Receptor (CAR) T cells targeting such antigens. Inspired by natural ultrasensitive response circuits, we engineer a two-step positive feedback circuit that allows T cells to discriminate targets based on a sigmoidal antigen density threshold. In this circuit, a low affinity SynNotch receptor for HER2 controls the expression of a high affinity CAR for HER2. Increasing HER2 density thus has cooperative effects on T cells it both increases CAR expression and activation leading to a sigmoidal response. T Cells with this circuit show sharp discrimination between target cells expressing normal and disease levels of HER2, both in vitro and in vivo. One Sentence SummaryA two-step positive feedback circuit generates engineered T cells capable of killing target cells with an ultrasensitive antigen density threshold.

synthetic biology↗