Lingxue Niu

Red light optogenetic systems are in high demand for the precise control of gene expression for gene- and cell-based therapies. Here, we report a red/far-red light-inducible photoswitch (REDLIP) system based on the chimeric photosensory protein FnBphP (Fn-REDLIP) or PnBphP (Pn-REDLIP) and their interaction partner LDB3, which enables efficient dynamic regulation of gene expression with a timescale of seconds without exogenous administration of a chromophore in mammals. We use the REDLIP system to establish the REDLIP-mediated CRISPR-dCas9 (REDLIPcas) system, enabling optogenetic activation of endogenous target genes in mammalian cells and mice. The REDLIP system is small enough to support packaging into adeno-associated viruses (AAVs), facilitating its therapeutic application. Demonstrating its capacity to treat metabolic diseases, we show that an AAV-delivered Fn-REDLIP system achieved optogenetic control of insulin expression to effectively lower blood glucose levels in type 1 diabetes model mice and control an anti-obesity therapeutic protein (thymic stromal lymphopoietin, TSLP) to reduce body weight in obesity model mice. REDLIP is a compact and sensitive optogenetic tool for reversible and non-invasive control that can facilitate basic biological and biomedical research. Red light optogenetic systems are in high demand for therapeutic applications. Here, the authors introduce REDLIP, a red-light-inducible system that enables rapid gene regulation without external chromophores, effectively modulating insulin and anti-obesity protein expression in disease models.

Abstract Induced pluripotent stem cells (iPSCs) share similar cellular features and various antigens profiles with cancer cells. Leveraging these characteristics, iPSCs hold great promise for developing wide‐spectrum vaccines against cancers. In practice, iPSCs are typically combined with immune adjuvants to enhance antitumor immune responses; however, traditional adjuvants lack controllability and can induce systemic toxicity, which has limited their broad application. Here, a r ed/far‐red light‐controlled i PSC‐based va ccine (RIVA) based on the chimeric photosensory protein FnBphP and its interaction partner LDB3 is developed; RIVA preserves the intrinsic tumor antigens of iPSCs and enables optogenetic control of an immune adjuvant's (IFN‐β) expression under red light illumination. Experiments in multiple mouse tumor models demonstrate that RIVA inhibits tumor growth and improves animal survival in prophylactic and therapeutic settings, including against pulmonary metastatic 4T1 breast cancer. RIVA efficiently stimulates dendritic cell maturation, eliciting innate immune activation effects through NK cells and elicit adaptive immune anti‐tumor responses through CD4 + and CD8 + T cells. Moreover, RIVA protects animals against tumor re‐challenge by inducing strong immunological memory, with minimal systemic toxicity. This study demonstrates RIVA as an effective optogenetic approach for developing safe multi‐antigen vaccines for the prevention and treatment of cancer.

Abstract Red light optogenetic systems are in high demand for the precise control of gene expression for gene- and cell-based therapies. Here, we report a red /far-red light-inducible p hotoswitch (REDLIP) system based on the chimeric photosensory protein FnBphP (Fn-REDLIP) or PnBphP (Pn-REDLIP) and their interaction partner LDB3, which enables efficient dynamic regulation of gene expression with a timescale of seconds without exogenous administration of a chromophore in mammals. We used the REDLIP system to establish the REDLIP-mediated CRISPR-dCas9 (REDLIP cas ) system, enabling optogenetic activation of endogenous target genes in mammalian cells and mice. The REDLIP system is small enough to support packaging into adeno-associated viruses (AAVs), facilitating its therapeutic application. Demonstrating its capacity to treat metabolic diseases, we show that an AAV-delivered Fn-REDLIP system achieved optogenetic control of insulin expression to effectively lower blood glucose levels in type 1 diabetes model mice and control an anti-obesity therapeutic protein (thymic stromal lymphopoietin, TSLP) to reduce body weight in obesity model mice. REDLIP is a compact and sensitive optogenetic tool for reversible and non-invasive control that can facilitate basic biological and biomedical research.