Curated Optogenetic Publication Database

Abstract: Genetically engineered bacteria have aroused attention as micro-nano drug delivery systems in situ. However, conventional designs of engineered bacteria usually function constantly or autonomously, which might be non-specific or imprecise. Therefore, designing and optimizing in situ control strategy are important methodological progress for therapeutic researches of intestinal engineered bacteria. Here, a micro-nano optogenetic system based on probiotic was developed combining microelectronics, nanotechnology, and synthetic biology to achieve in situ controllable drug delivery. Firstly, optogenetic engineered Lactococcus lactis was orally administrated in the intestinal tract. A wearable optical device was designed to control optical signals remotely. Then, L. lactis could be customized to secrete peptides according to optical signals. As an example, optogenetic L. lactis system can be constructed to secrete glucagon-like peptide-1 (GLP-1) under the control of the wearable optical device to regulate metabolism. To improve the half-life of GLP-1 in vivo, Fc-domain fused GLP-1 was optimally used. Using this strategy, blood glucose, weight, and other features were well controlled in rats and mice models. Furthermore, upconversion microcapsules were introduced to increase the excitation wavelength of the optogenetic system for better penetrability. This strategy has biomedical potential to expand the toolbox for intestinal engineered bacteria.

Abstract: Regulation of receptor tyrosine kinase (RTK) activity is necessary for studying cell signaling pathways in health and disease. We developed a generalized approach for engineering RTKs optically controlled with far-red light. We targeted the bacterial phytochrome DrBphP to the cell surface and allowed its light-induced conformational changes to be transmitted across the plasma membrane via transmembrane helices to intracellular RTK domains. Systematic optimization of these constructs has resulted in optically regulated epidermal growth factor receptor, HER2, TrkA, TrkB, FGFR1, IR1, cKIT and cMet, named eDrRTKs. eDrRTKs induced downstream signaling in mammalian cells in tens of seconds. The ability to activate eDrRTKs with far-red light enabled spectral multiplexing with fluorescent probes operating in a shorter spectral range, allowing for all-optical assays. We validated eDrTrkB performance in mice and found that minimally invasive stimulation in the neocortex with penetrating via skull far-red light-induced neural activity, early immediate gene expression and affected sleep patterns.

Abstract: The discovery of the gut-brain axis has proven that brain functions can be affected by the gut microbiota's metabolites, so there are significant opportunities to explore new tools to regulate gut microbiota and thus work on the brain functions. Meanwhile, engineered bacteria as oral live biotherapeutic agents to regulate the host's healthy homeostasis have attracted much attention in microbial therapy. However, whether this strategy is able to remotely regulate the host's brain function in vivo has not been investigated. Here, we engineered three blue-light-responsive probiotics as oral live biotherapeutic agents. They are spatiotemporally delivered and controlled by the upconversion optogenetic micro-nano system. This micro-nano system promotes the small intestine targeting and production of the exogenous L. lactis in the intestines, which realizes precise manipulation of brain functions including anxiety behavior, Parkinson's disease, and vagal afferent. The noninvasive and real-time probiotic intervention strategy makes the communiation from the gut to the host more controllable, which will enable the potential for engineered microbes accurately and effectively regulating a host's health.

Abstract: The enteroendocrine system plays an important role in metabolism. The gut microbiome regulates enteroendocrine in an extensive way, arousing attention in biomedicine. However, conventional strategies of enteroendocrine regulation via gut microbiome are usually non-specific or imprecise. Here, an optogenetic operated probiotics system was developed combining synthetic biology and flexible electronics to achieve in situ controllable secretion to mimic enteroendocrine. Firstly, optogenetic engineered Lactococcus lactis (L. lactis) were administrated in the intestinal tract. A wearable optogenetic device was designed to control optical signals remotely. Then, L. lactis could secrete enteroendocrine hormone according to optical signals. As an example, optogenetic L. lactis could secrete glucagon-like peptide-1(GLP-1) under the control of the wearable optogenetic device. To improve the half-life of GLP-1 in vivo, the Fc domain from immunoglobulin was fused. Treated with this strategy, blood glucose, weight and other features were relatively well controlled in rats and mice models. Furthermore, up-conversion microcapsules were introduced to increase the excitation wavelength of the optogenetic system for better penetrability. This strategy has biomedical potential in metabolic diseases therapy by mimicking enteroendocrine.

Abstract: Recombinant bacterial colonization plays an indispensable role in disease prevention, alleviation, and treatment. Successful application mainly depends on whether bacteria can efficiently spatiotemporally colonize the host gut. However, a primary limitation of existing methods is the lack of precise spatiotemporal regulation, resulting in uncontrolled methods that are less effective. Herein, we design upconversion microgels (UCMs) to convert near-infrared light (NIR) into blue light to activate recombinant light-responsive bacteria (Lresb) in vivo, where autocrine "functional cellular glues" made of adhesive proteins assist Lresb inefficiently colonizing the gut. The programmable engineering platform is further developed for the controlled and effective colonization of Escherichia coli Nissle 1917 (EcN) in the gut. The colonizing bacteria effectively alleviate DSS-induced colitis in mice. We anticipate that this approach could facilitate the clinical application of engineered microbial therapeutics to accurately and effectively regulate host health.

Abstract: Ulcerative colitis (UC) is a relapsing disorder characterized by chronic inflammation of the intestinal tract. However, the home care of UC based on remote monitoring, due to the operational complexity and time-consuming procedure, restrain its widespread applications. Here we constructed an optotheranostic nanosystem for self-diagnosis and long-acting mitigations of UC at home. The system included two major modules: (i) A disease prescreening module mediated by smartphone optical sensing. (ii) Disease real-time intervention module mediated by an optogenetic engineered bacteria system. Recombinant Escherichia coli Nissle 1917 (EcN) secreted interleukin-10 (IL-10) could downregulate inflammatory cascades and matrix metalloproteinases; it is a candidate for use in the therapeutic intervention of UC. The results showed that the Detector was able to analyze, report, and share the detection results in less than 1 min, and the limit of detection was 15 ng·mL-1. Besides, the IL-10-secreting EcN treatment suppressed the intestinal inflammatory response in UC mice and protected the intestinal mucosa against injury. The optotheranostic nanosystems enabled solutions to diagnose and treat disease at home, which promotes a mobile health service development.

Abstract: Chemical molecules specifically secreted into the blood and targeted tissues by intestinal microbiota can effectively affect the associated functions of the intestine especially immunity, representing a new strategy for immune-related diseases. However, proper ways of regulating the secretion metabolism of specific strains still remain to be established. In this article, an upconversion optogenetic micro-nanosystem was constructed to effectively regulate the specific secretion of engineered bacteria. The system included two major modules: (i) Modification of secretory light-responsive engineered bacteria. (ii) Optical sensing mediated by upconversion optogenetic micro-nanosystem. This system could regulate the efficient secretion of immune factors by engineered bacteria through optical manipulation. Inflammatory bowel disease and subcutaneously transplanted tumors were selected to verify the effectiveness of the system. Our results showed that the endogenous factor TGF-β1 could be controllably secreted to suppress the intestinal inflammatory response. Additionally, regulatory secretion of IFN-γ was promoted to slow the progression of B16F10 tumor.