Periodic Reporting for period 2 - DEEPER (DEEP BRAIN PHOTONIC TOOLS FOR CELL-TYPE SPECIFIC TARGETING OF NEURAL DISEASES)
Berichtszeitraum: 2022-07-01 bis 2023-12-31
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).
DEEPER aims to enhance the ability of clinical experts to access deep brain regions effectively and study the molecular and cellular dysfunctions involved in neurological diseases.
In the initial 18 project months, partners focused on creating genetically-encoded sensors, optogenetic and photo pharmacological actuators for diverse neuromodulation and neural activity recording in deep-brain circuits. Recent achievements include tracking dopamine, norepinephrine, and serotonin release in the brain. Simultaneously, a new set of optogenetic actuators for in vivo neurosignaling control was developed. Additionally, a small library of photoswitchable drugs is being created for potential light-based treatment of chronic inflammatory pain.
Tapered fiber-based optrodes for simultaneous optical control and electrophysiological readout with minimal photoelectric noise have been achieved and two micrometer-sized light-emitting devices (µLEDs) were successfully integrated with microelectrodes for extracellular recording.
A laser system set-up was developed for a three-photon microscope Improving image capacity in a multi-mode fiber (MMF)-based endo-microscope with integrated electrodes for simultaneous imaging and electrophysiology.
For clinically relevant experiments on addiction, chronic pain, Alzheimer’s, and psychiatric disorders (depression, schizophrenia, autism), DEEPER partners developed techniques to study specific neurotransmitters/modulators' role in compulsive behavior in drug addiction (e.g. fentanyl, cocaine) using fiber photometry. Studying developmental miswiring mechanisms in large-scale networks of schizophrenia and autism mouse models involved developing and testing probes suitable for freely moving neonatal and juvenile animals.
In the second 18 months of DEEPER, further development and application of new molecular tools, implantable probes, and deep brain microscopy/endoscopy systems have occurred in collaboration with clinical experts.
Ultrasensitive green and red fluorescent neurotransmitter sensors were created and genomic sequences encoding opsins for synaptic transmission were identified. Photoswitchable compound libraries targeting different receptors, including compounds activated by red light were developed.
Microfabrication allowed electrode integration on micropatterned tapered optical fiber, improving light delivery and collection performance. A dual-color silicon probe with micro-LEDs and microelectrodes for neural activity control was developed. The integration of advanced probe designs with microelectrodes and fluidic channels on flexible substrates for localized drug administration and optimal signal recording was proposed and developed.
Minimally invasive endoscopes with improved imaging capabilities (using GRIN lenses) and electrophysiological recording and stimulation using a three-photon holographic excitation microscope were tested in mice. A two-photon fiber-based micro-endoscope (2P-FENDO) with an extended field of view was developed.
Preliminary system tests with a new wireless head stage, μLaser array, and systems for coupling two-photon microscopy and tapered optical fiber detection were successfully carried out. A control and synchronization software, named "DeeperScope" was developed allowing to customize key parameters for data acquisition.
Mouse fiber photometry experiments showed regional drug responses in the striatum, aiming to understand circuit adaptations driving compulsive behaviors and recording dopamine release in freely moving mice. A proof-of-principle study monitoring Alzheimer's disease pathology, schizophrenia and autism was conducted. In studying neurodevelopmental disorders, the project discovered non-linear reorganization of excitatory neurons during adolescence.
In the initial 18 project months, partners focused on creating genetically-encoded sensors, optogenetic and photo pharmacological actuators for diverse neuromodulation and neural activity recording in deep-brain circuits. Recent achievements include tracking dopamine, norepinephrine, and serotonin release in the brain. Simultaneously, a new set of optogenetic actuators for in vivo neurosignaling control was developed. Additionally, a small library of photoswitchable drugs is being created for potential light-based treatment of chronic inflammatory pain.
Tapered fiber-based optrodes for simultaneous optical control and electrophysiological readout with minimal photoelectric noise have been achieved and two micrometer-sized light-emitting devices (µLEDs) were successfully integrated with microelectrodes for extracellular recording.
A laser system set-up was developed for a three-photon microscope Improving image capacity in a multi-mode fiber (MMF)-based endo-microscope with integrated electrodes for simultaneous imaging and electrophysiology.
For clinically relevant experiments on addiction, chronic pain, Alzheimer’s, and psychiatric disorders (depression, schizophrenia, autism), DEEPER partners developed techniques to study specific neurotransmitters/modulators' role in compulsive behavior in drug addiction (e.g. fentanyl, cocaine) using fiber photometry. Studying developmental miswiring mechanisms in large-scale networks of schizophrenia and autism mouse models involved developing and testing probes suitable for freely moving neonatal and juvenile animals.
In the second 18 months of DEEPER, further development and application of new molecular tools, implantable probes, and deep brain microscopy/endoscopy systems have occurred in collaboration with clinical experts.
Ultrasensitive green and red fluorescent neurotransmitter sensors were created and genomic sequences encoding opsins for synaptic transmission were identified. Photoswitchable compound libraries targeting different receptors, including compounds activated by red light were developed.
Microfabrication allowed electrode integration on micropatterned tapered optical fiber, improving light delivery and collection performance. A dual-color silicon probe with micro-LEDs and microelectrodes for neural activity control was developed. The integration of advanced probe designs with microelectrodes and fluidic channels on flexible substrates for localized drug administration and optimal signal recording was proposed and developed.
Minimally invasive endoscopes with improved imaging capabilities (using GRIN lenses) and electrophysiological recording and stimulation using a three-photon holographic excitation microscope were tested in mice. A two-photon fiber-based micro-endoscope (2P-FENDO) with an extended field of view was developed.
Preliminary system tests with a new wireless head stage, μLaser array, and systems for coupling two-photon microscopy and tapered optical fiber detection were successfully carried out. A control and synchronization software, named "DeeperScope" was developed allowing to customize key parameters for data acquisition.
Mouse fiber photometry experiments showed regional drug responses in the striatum, aiming to understand circuit adaptations driving compulsive behaviors and recording dopamine release in freely moving mice. A proof-of-principle study monitoring Alzheimer's disease pathology, schizophrenia and autism was conducted. In studying neurodevelopmental disorders, the project discovered non-linear reorganization of excitatory neurons during adolescence.
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).