Current Progress and Future Outlook for Synthetic Gene Circuits in Cardiovascular Therapy

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  Figure 1. Illustrative examples of synthetic gene circuit architectures for cardiovascular applications (a) A closed-loop circuit for heart failure in which a BNP promoter, activated by cardiac wall stress, drives expression of a therapeutic shRNA that silences PP1β. This relieves PP1β-mediated suppression of SERCA2a, restoring Ca2+ handling. Since the therapeutic output alleviates the stress that drives promoter activation, the circuit self-regulates through host physiology (left: diseased state; right: relieved stress). (b) A closed-loop cholesterol-sensing circuit in which a constitutive promoter drives a PCSK9 inhibitor downstream of an SRE element. Under high cholesterol conditions, the KRAB–SREBP fusion protein is retained, permitting therapeutic expression. The resulting PCSK9 inhibition restores LDL receptor levels and reduces circulating cholesterol (left: atherosclerotic artery; right: cleared artery). (c) Examples of Boolean logic gates designed to classify cells within a heterogeneous cardiac microenvironment (left). An OR gate example that uses tandem promoters (P1/P2) to drive a single gene of interest, alongside an AND gate example that requires co-expression of split…

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  Figure 2. A proposed data-driven translational pipeline for cardiovascular synthetic biology. Adapting the traditional DBTL cycle, this three-node framework is tailored to cardiac applications, with examples at each node. (a) The complexity of multi-pathway cardiomyopathies can be approached by utilizing gene regulatory network (GRN) inference and foundation models for in silico target discovery, alongside high-throughput machine learning platforms (e.g., CLASSIC) to aid in circuit composability. (b) Viral packaging limits and baseline delivery noise can be addressed through dual-vector AAV fragmentation, targeted large-capacity lipid nanoparticles (LNPs), and the integration of dosage-compensating architectures (e.g., DIMMERs) can promote more uniform expression. (c) The interspecies physiological discordance between rodents and humans necessitates shifting early-stage in vitro validation toward human iPSC-derived microtissues and late-stage in vivo testing toward genetically engineered porcine models.