Optogenetic engineering of STING signaling allows remote immunomodulation to enhance cancer immunotherapy

Chlorin e6 and BLZ945 Based Self-Assembly for Photodynamic Immunotherapy Through Immunogenic Tumor Induction and Tumor-Associated Macrophage Depletion

Immunotherapeutic effect is restricted by the nonimmunogenic tumor phenotype and immunosuppression behaviors of tumor-associated macrophages (TAMs). In this work, a drug self-assembly (designated as CeBLZ) is fabricated based on chlorin e6 (Ce6) and BLZ945 to activate photodynamic immunotherapy through tumor immunogenic induction and tumor-associated macrophage depletion. It is found that Ce6 tends to assemble with BLZ945 without any drug excipients, which can enhance the cellular uptake, tumor penetration, and blood circulation behaviors. The robust photodynamic therapy effect of CeBLZ efficiently suppresses the primary tumor growth and also triggers immunogenic cell death to reverse the nonimmunogenic tumor phenotype. Moreover, CeBLZ can deplete TAMs in tumor tissues to reverse the immunosuppression microenvironment, activating abscopal effect for distant tumor inhibition. In vitro and in vivo results confirm the superior antitumor effect of CeBLZ with negligible side effect, which might promote the development of sophisticated drug combinations for systematic tumor management.

Development of an optogenetics tool, Opto-RANK, for control of osteoclast differentiation using blue light

Optogenetics enables precise regulation of intracellular signaling in target cells. However, the application of optogenetics to induce the differentiation of precursor cells and generate mature cells with specific functions has not yet been fully explored. Here, we focused on osteoclasts, which play an important role in bone remodeling, to develop a novel optogenetics tool, Opto-RANK, which can manipulate intracellular signals involved in osteoclast differentiation and maturation using blue light. We engineered Opto-RANK variants, Opto-RANKc and Opto-RANKm, and generated stable cell lines through retroviral transduction. Differentiation was induced by blue light, and various assays were conducted for functional analysis. Osteoclast precursor cells expressing Opto-RANK differentiated into multinucleated giant cells on light exposure and displayed upregulation of genes normally induced in differentiated osteoclasts. Furthermore, the differentiated cells exhibited bone-resorbing activities, with the possibility of spatial control of the resorption by targeted light illumination. These results suggested that Opto-RANK cells differentiated by light possess the features of osteoclasts, both morphological and functional. Thus, Opto-RANK should be useful for detailed spatiotemporal analysis of intracellular signaling during osteoclast differentiation and the development of new therapies for various bone diseases.