The application of current channelrhodopsin-based optogenetic tools is limited by the lack of strict ion selectivity and the inability to extend the spectra sensitivity into the near-infrared (NIR) tissue transmissible range. Here we present an NIR-stimulable optogenetic platform (termed 'Opto-CRAC') that selectively and remotely controls Ca2+ oscillations and Ca2+-responsive gene expression to regulate the function of non-excitable cells, including T lymphocytes, macrophages and dendritic cells. When coupled to upconversion nanoparticles, the optogenetic operation window is shifted from the visible range to NIR wavelengths to enable wireless photoactivation of Ca2+-dependent signaling and optogenetic modulation of immunoinflammatory responses. In a mouse model of melanoma by using ovalbumin as surrogate tumor antigen, Opto-CRAC has been shown to act as a genetically-encoded 'photoactivatable adjuvant' to improve antigen-specific immune responses to specifically destruct tumor cells. Our study represents a solid step forward towards the goal of achieving remote and wireless control of Ca2+-modulated activities with tailored function.DOI: http://dx.doi.org/10.7554/eLife.10024.001

FDA-approved chimeric antigen receptor (CAR) T cell-based immunotherapy has shown curative potential in patients with hematological malignancies. However, owing to the lack of control over the location and duration of anti-tumor immune response, CAR T-cell therapy still faces significant safety challenges arising from cytokine release syndrome and on-target off-tumor toxicity. Herein, we present the design of light-switchable CAR T-cells (designated “LiCAR-T”) that allow real-time photo-tunable activation of therapeutic T cells to precisely induce tumor cell killing. When coupled with imaging-guided, surgically removable upconversion nanoplates (UCNPs) that have enhanced near infrared (NIR)-to-blue upconversion luminescence as miniature deep tissue photon-transducers, LiCAR T-cells enable both spatial and temporal control over T cell-mediated anti-tumor therapeutic activity in vivo with greatly mitigated side effects. Our nano-optogenetic immunomodulation platform not only provides a unique approach to interrogate CAR-mediated anti-tumor immunity, but also sets the stage for developing precision medicine to deliver personalized anti-cancer therapy.

Tet-mediated DNA demethylation plays an important role in shaping the epigenetic landscape and chromatin accessibility to control gene expression. While several studies demonstrated pivotal roles of Tet in regulating embryonic development, little is known about their functions in heart development. Here we analyze DNA methylation and hydroxymethylation dynamics during early cardiac development in both human and mice. We find that cardiac-specific deletion of Tet2 and Tet3 in mice (Tet2/3-DKO) leads to ventricular non-compaction cardiomyopathy (NCC) with embryonic lethality. Single-cell RNA-seq analyses reveal a reduction in cardiomyocyte numbers and transcriptional reprogramming in cardiac tissues upon Tet2/3 depletion. Impaired DNA demethylation and reduced chromatin accessibility in Tet2/3-DKO mice further compromised Ying-yang1 (YY1) binding to its genomic targets, and perturbed high-order chromatin organization at key genes involved in heart development. Our studies provide evidence of the physiological role of Tet in regulating DNA methylation dynamics and chromatin organization during early heart development.