Periodic Reporting for period 1 - DEEPER (DEEP BRAIN PHOTONIC TOOLS FOR CELL-TYPE SPECIFIC TARGETING OF NEURAL DISEASES)
Reporting period: 2021-01-01 to 2022-06-30
DEEPER project (Deep Brain Photonic Tools for Cell-Type Specific Targeting of Neural Diseases) put together technological, neuroscientific and clinical experts with innovative start-ups and leading companies with the aim of developing photonic tools for imaging and manipulating neuronal activity in deep brain regions. The long-term vision of the project is to exploit photonics for meeting medical and research needs in revealing the molecular and cellular dysfunctions underlying the pathogenesis of neurological diseases.
Existing medical tools fail in giving a detailed, high-resolution, dynamic picture of sub-cortical brain structures in behaving animals. It is in this deep region that the pathological behaviour of neurotransmitters such as dopamine, serotonin, and norepinephrine alter the function of brain circuits. This is at the origin of neurological illness with a dramatic social impact such as addiction, chronic pain, Alzheimer’s disease, depression, schizophrenia, and autism spectrum disorder.
The project consortium expects to develop, through neurophotonic techniques, less invasive and more effective treatments for brain neurological conditions. All developed tools will be tested in well-defined and ethically approved animal models of human disease, assessing their suitability for routine use in neuroscience laboratories and their clinical translational potential.
The consortium, thanks to the developed technologies, will push the construction of a value chain that will strengthen Europe’s industrial position in the biophotonics market for microscopy and endoscopy and will accelerate to market the developed tools and project results, via startups and market leaders. This acceleration to commercialization will occur in all the areas covered by the project (genetic tools, pharmaceutical tools, implants, and advanced optical instruments).
Existing medical tools fail in giving a detailed, high-resolution, dynamic picture of sub-cortical brain structures in behaving animals. It is in this deep region that the pathological behaviour of neurotransmitters such as dopamine, serotonin, and norepinephrine alter the function of brain circuits. This is at the origin of neurological illness with a dramatic social impact such as addiction, chronic pain, Alzheimer’s disease, depression, schizophrenia, and autism spectrum disorder.
The project consortium expects to develop, through neurophotonic techniques, less invasive and more effective treatments for brain neurological conditions. All developed tools will be tested in well-defined and ethically approved animal models of human disease, assessing their suitability for routine use in neuroscience laboratories and their clinical translational potential.
The consortium, thanks to the developed technologies, will push the construction of a value chain that will strengthen Europe’s industrial position in the biophotonics market for microscopy and endoscopy and will accelerate to market the developed tools and project results, via startups and market leaders. This acceleration to commercialization will occur in all the areas covered by the project (genetic tools, pharmaceutical tools, implants, and advanced optical instruments).
The activities have been mostly devoted to develop new technology, both molecular tools, implantable probes and imaging systems, for allowing the clinical experts of the DEEPER project to reach deep brain regions more effectively and for studying the molecular and cellular dysfunctions underlying the pathogenesis of neurological diseases. Some of the developed tools have been already made available to the international neuroscience community.
During the first 18 months of the project, the partners have worked on developing new genetically-encoded sensors and optogenetic and photo pharmacological actuators which will enable different modalities of neuromodulation and recording of neural activity in deep-brain circuits. The tracking of the release of dopamine, norepinephrine and serotonin in the brain has been recently reported. In parallel, a new range of optogenetic actuators to control neurosignaling in vivo have been developed. Moreover, a small library of new photoswitchable drugs is beeing realized to potentially treat chronic inflammatory pain with light.
Tapered fibers-based optrodes for optically control of neural activity and simultaneous electrophysiological readout have been obtained with substantially absent photoelectric noise. Moreover, two different micrometer-sized light emitting (µLED) devices have been integrated together with micro electrodes for extracellular recording. The integration of fluidic channels together with µLED on the same implantable probe was implemented through novel high-yield fabrication processes. A synergic collaboration between partners is allowing the preliminary assembling of tapered fiber-µLED integrated probe to design and realize wireless headstages for the different implantable probes.
A laser system is being setup for designing the optical path of a three-photon microscope. Moreover, image optimization in multi-mode fibre (MMF)-based endo-microscope produced a higher imaging capacity and electrodes are being integrated for simoultaneous imaging and electrophysiology. Optical aberration have been successfully reduced in GRIN lens based endoscopes and a new two-photon fibre-based micro-endoscope has been realised for the study of neuronal activity in freely moving mice.
Regarding clinically relevant experiments for studying addiction, chronic pain, Alzheimer’s disease and psychiatric disorders (depression, schizophrenia, and autism), DEEPER partners realized technique to investigate the role of specific neurotransmitters/modulators in the establishment of compulsive behavior in drug addiction by fiber photometry for drugs such as fentanyl and cocaine. A multi-colour tapered fiber setup is currently being designed for allowing imaging of dopamine release and calcium activity along the dorso-ventral striatal axes in freely moving mice. The monitoring of the release of serotonin and norepinephrine in behaving animals and the definition of the conditions of their release is being studied to better characterize the organization of noradrenergic and serotonergic input to the spinal dorsal horn and to establish means to selectively manipulate them in vivo. A photometry approach which allows monitoring of AD pathology across multiple brain regions in vivo is being developed in freely behaving mice, in conjunction with tapered fibers and optical setups.
The mechanisms of developmental miswiring in large scale networks in schizophrenia and autism mouse models has been studied by developing and testing probes suitable for neonatal and juvenile animals during freely moving.
During the first 18 months of the project, the partners have worked on developing new genetically-encoded sensors and optogenetic and photo pharmacological actuators which will enable different modalities of neuromodulation and recording of neural activity in deep-brain circuits. The tracking of the release of dopamine, norepinephrine and serotonin in the brain has been recently reported. In parallel, a new range of optogenetic actuators to control neurosignaling in vivo have been developed. Moreover, a small library of new photoswitchable drugs is beeing realized to potentially treat chronic inflammatory pain with light.
Tapered fibers-based optrodes for optically control of neural activity and simultaneous electrophysiological readout have been obtained with substantially absent photoelectric noise. Moreover, two different micrometer-sized light emitting (µLED) devices have been integrated together with micro electrodes for extracellular recording. The integration of fluidic channels together with µLED on the same implantable probe was implemented through novel high-yield fabrication processes. A synergic collaboration between partners is allowing the preliminary assembling of tapered fiber-µLED integrated probe to design and realize wireless headstages for the different implantable probes.
A laser system is being setup for designing the optical path of a three-photon microscope. Moreover, image optimization in multi-mode fibre (MMF)-based endo-microscope produced a higher imaging capacity and electrodes are being integrated for simoultaneous imaging and electrophysiology. Optical aberration have been successfully reduced in GRIN lens based endoscopes and a new two-photon fibre-based micro-endoscope has been realised for the study of neuronal activity in freely moving mice.
Regarding clinically relevant experiments for studying addiction, chronic pain, Alzheimer’s disease and psychiatric disorders (depression, schizophrenia, and autism), DEEPER partners realized technique to investigate the role of specific neurotransmitters/modulators in the establishment of compulsive behavior in drug addiction by fiber photometry for drugs such as fentanyl and cocaine. A multi-colour tapered fiber setup is currently being designed for allowing imaging of dopamine release and calcium activity along the dorso-ventral striatal axes in freely moving mice. The monitoring of the release of serotonin and norepinephrine in behaving animals and the definition of the conditions of their release is being studied to better characterize the organization of noradrenergic and serotonergic input to the spinal dorsal horn and to establish means to selectively manipulate them in vivo. A photometry approach which allows monitoring of AD pathology across multiple brain regions in vivo is being developed in freely behaving mice, in conjunction with tapered fibers and optical setups.
The mechanisms of developmental miswiring in large scale networks in schizophrenia and autism mouse models has been studied by developing and testing probes suitable for neonatal and juvenile animals during freely moving.
The advances beyond the state-of-the-art in DEEPER is resulting in a number of unprecedented key exploitable results and market products: (i) HDlight indications are expected to increase ~3 times the dynamic range, to introduce new monitored neurotransmitters and red-shift operative wavelengths; (ii) the consortium will introduce presynaptic silencing tools with 10-times lower activation threshold and light-gated channels with ~5 times higher photocurrent; (iii) DEEPER will make available photoswitchable drugs for controlling dopamine, adrenaline, GABA and serotonin; (iv) depth-selective fiber photometry is providing spatial-resolution in sub-cortical structures of free- moving mice; (v) μLEDs density will be at least doubled together with the introduction of multiple microfluidic channels and multichannel electrophysiology; (vi) we will provide the first systems for correlating functional fluorescence and electrophysiology signals with spatial resolution at both population-wide scale and single cell resolution.
DEEPER is developing the novel concept of multifunctional multi-photon microscopy by combining advanced two-photon and three- photon excitation strategies with multifunctional neural interfaces capable endoscopic detection of functional fluorescence and electro-physiological recordings.
At the same time, the consortium is working to demonstrate the first wireless controlled, integrated, lightweight (< 2g) headstage for depth resolved fiber photometry, optogenetics and electrophysiology recordings in freely moving animals.
These new technologies and protocols are being applied to specific pathologies with the ambition of shedding new light on the mechanism of neurological (addiction, pain, AD) and psychiatric disorders (depression, schizophrenia, autism).
DEEPER is developing the novel concept of multifunctional multi-photon microscopy by combining advanced two-photon and three- photon excitation strategies with multifunctional neural interfaces capable endoscopic detection of functional fluorescence and electro-physiological recordings.
At the same time, the consortium is working to demonstrate the first wireless controlled, integrated, lightweight (< 2g) headstage for depth resolved fiber photometry, optogenetics and electrophysiology recordings in freely moving animals.
These new technologies and protocols are being applied to specific pathologies with the ambition of shedding new light on the mechanism of neurological (addiction, pain, AD) and psychiatric disorders (depression, schizophrenia, autism).