Open and remotely accessible Neuroplatform for research in wetware computing.

Wetware computing and organoid intelligence is an emerging research field at the intersection of electrophysiology and artificial intelligence. The core concept involves using living neurons to perform computations, similar to how Artificial Neural Networks (ANNs) are used today. However, unlike ANNs, where updating digital tensors (weights) can instantly modify network responses, entirely new methods must be developed for neural networks using biological neurons. Discovering these methods is challenging and requires a system capable of conducting numerous experiments, ideally accessible to researchers worldwide. For this reason, we developed a hardware and software system that allows for electrophysiological experiments on an unmatched scale. The Neuroplatform enables researchers to run experiments on neural organoids with a lifetime of even more than 100 days. To do so, we streamlined the experimental process to quickly produce new organoids, monitor action potentials 24/7, and provide electrical stimulations. We also designed a microfluidic system that allows for fully automated medium flow and change, thus reducing the disruptions by physical interventions in the incubator and ensuring stable environmental conditions. Over the past three years, the Neuroplatform was utilized with over 1,000 brain organoids, enabling the collection of more than 18 terabytes of data. A dedicated Application Programming Interface (API) has been developed to conduct remote research directly via our Python library or using interactive compute such as Jupyter Notebooks. In addition to electrophysiological operations, our API also controls pumps, digital cameras and UV lights for molecule uncaging. This allows for the execution of complex 24/7 experiments, including closed-loop strategies and processing using the latest deep learning or reinforcement learning libraries. Furthermore, the infrastructure supports entirely remote use. Currently in 2024, the system is freely available for research purposes, and numerous research groups have begun using it for their experiments. This article outlines the system's architecture and provides specific examples of experiments and results.

Spatiotemporal PET Imaging Reveals Differences in CAR-T Tumor Retention in Triple-Negative Breast Cancer Models.

Chimeric antigen receptor T cell therapy (CAR-T) has been rolled out as a new treatment for hematological malignancies. For solid tumor treatment, CAR-T has been disappointing so far. Challenges include the quantification of CAR-T trafficking, expansion and retention in tumors, activity at target sites, toxicities, and long-term CAR-T survival. Non-invasive serial in vivo imaging of CAR-T using reporter genes can address several of these challenges. For clinical use, a non-immunogenic reporter that is detectable with exquisite sensitivity by positron emission tomography (PET) using a clinically available non-toxic radiotracer would be beneficial. Here, we employed the human sodium iodide symporter to non-invasively quantify tumor retention of pan-ErbB family targeted CAR-T by PET. We generated and characterized traceable CAR T cells and examined potential negative effects of radionuclide reporter use. We applied our platform to two different triple-negative breast cancer (TNBC) models and unexpectedly observed pronounced differences in CAR-T tumor retention by PET/CT (computed tomography) and confirmed data ex vivo. CAR-T tumor retention inversely correlated with immune checkpoint expression in the TNBC models. Our platform enables highly sensitive non-invasive PET tracking of CAR-T thereby addressing a fundamental unmet need in CAR-T development and offering to provide missing information needed for future clinical CAR-T imaging.

Reporter gene imaging and its role in imaging-based drug development.

Reporter gene imaging (RGI) is described as the methodology that involves imaging of the encoding proteins that can be used as surrogate markers when fused with regulatory regions of the gene of interest. It provides a means to indirectly monitor molecular processes that are implicated in the pathophysiology of several diseases. The modalities utilized in RGI include MRI, PET, SPECT, as well as optical imaging modalities, such as bioluminescence and fluorescence. RGI provides a highly specific way to qualitatively and quantitatively assess cell targeting, transfection, protein expression and other intracellular processes, which are valuable for pharmacodynamic and pharmacokinetic assessment of cellular, gene and oncolytic viral therapeutics.

Reporter gene-engineering of human induced pluripotent stem cells during differentiation renders in vivo traceable hepatocyte-like cells accessible.

Primary hepatocyte transplantation (HTx) is a safe cell therapy for patients with liver disease, but wider application is circumvented by poor cell engraftment due to limitations in hepatocyte quality and transplantation strategies. Hepatocyte-like cells (HLCs) derived from human induced pluripotent stem cells (hiPSC) are considered a promising alternative but also require optimisation of transplantation and are often transplanted prior to full maturation. Whole-body in vivo imaging would be highly beneficial to assess engraftment non-invasively and monitor the transplanted cells in the short and long-term. Here we report a lentiviral transduction approach designed to engineer hiPSC-derived HLCs during differentiation. This strategy resulted in the successful production of sodium iodide symporter (NIS)-expressing HLCs that were functionally characterised, transplanted into mice, and subsequently imaged using radionuclide tomography.

Repeated social defeat induces transient glial activation and brain hypometabolism: A positron emission tomography imaging study.

Psychosocial stress is a risk factor for the development of depression. Recent evidence suggests that glial activation could contribute to the development of depressive-like behaviour. This study aimed to evaluate in vivo whether repeated social defeat (RSD) induces short- and long-term inflammatory and metabolic alterations in the brain through positron emission tomography (PET). Male Wistar rats ( n = 40) were exposed to RSD by dominant Long-Evans rats on five consecutive days. Behavioural and biochemical alterations were assessed at baseline, day 5/6 and day 24/25 after the RSD protocol. Glial activation (11C-PK11195 PET) and changes in brain metabolism (18F-FDG PET) were evaluated on day 6, 11 and 25 (short-term), and at 3 and 6 months (long-term). Defeated rats showed transient depressive- and anxiety-like behaviour, increased corticosterone and brain IL-1ß levels, as well as glial activation and brain hypometabolism in the first month after RSD. During the third- and six-month follow-up, no between-group differences in any investigated parameter were found. Therefore, non-invasive PET imaging demonstrated that RSD induces transient glial activation and reduces brain glucose metabolism in rats. These imaging findings were associated with stress-induced behavioural changes and support the hypothesis that neuroinflammation could be a contributing factor in the development of depression.

Therapeutic effects of dietary intervention on neuroinflammation and brain metabolism in a rat model of photothrombotic stroke.

INTRODUCTION: A possible target for stroke management is modulation of neuroinflammation. Evidence suggests that food components may exert anti-inflammatory properties and thus may reduce stroke-induced brain damage. AIM: To investigate the efficacy of a diet, containing anti-inflammatory ingredients, as treatment for focal ischemic brain damage induced by photothrombotic stroke in the somatosensory cortex of rats. RESULTS: Brain lesions were surrounded by strong astrogliosis on both day 7 and day 21 after stroke and were accompanied by a trend toward globally decreased glucose metabolism on day 7. The investigational diet applied 2 weeks before the ischemia did not affect astrocyte activation on day 7, but reduced it at day 21. The investigational diet applied immediately after the ischemia, increased astrocyte activation on day 7 and completely reversed this effect on day 21. Moreover, postischemic intervention increased glucose metabolism in somatosensory cortex ipsilateral to the lesion on day 7. CONCLUSION: This study reveals potentially beneficial effects of a diet containing elevated amounts of anti-inflammatory nutrients on the recovery from ischemic brain damage. Therefore, dietary intervention can be considered as an adjuvant therapy for recovery from this brain pathology.

Cousins at work: How combining medical with optical imaging enhances in vivo cell tracking.

Microscopy and medical imaging are related in their exploitation of electromagnetic waves, but were developed to satisfy differing needs, namely to observe small objects or to look inside subjects/objects, respectively. Together, these techniques can help elucidate complex biological processes and better understand health and disease. A current major challenge is to delineate mechanisms governing cell migration and tissue invasion in organismal development, the immune system and in human diseases such as cancer where the spatiotemporal tracking of small cell numbers in live animal models is extremely challenging. Multi-modal multi-scale in vivo cell tracking integrates medical and optical imaging. Fuelled by basic research in cancer biology and cell-based therapeutics, it has been enabled by technological advances providing enhanced resolution, sensitivity and multiplexing capabilities. Here, we review which imaging modalities have been successfully used for in vivo cell tracking and how this challenging task has benefitted from combining macroscopic with microscopic techniques.

Anti-inflammatory effects of rice bran components.

Neuroinflammation has been implicated in the pathology of various psychiatric and neurodegenerative disorders. Accumulating evidence suggests that food components can modulate inflammatory processes, and therefore it could be hypothesized that such nutrients might exhibit therapeutic efficacy against these brain diseases. Rice bran is often discarded as a waste product, although it contains a wide range of potentially useful substances. Several rice fiber components from rice bran have been described as having antiinflammatory properties. This review summarizes the evidence supporting a modulatory effect of rice fiber components on symptoms in several animal models for neuroinflammation. In vitro studies on immune cells and in vivo studies on nutritional intervention in animal models of central and peripheral inflammation are discussed in the context of the potential use of rice fiber components for prevention and treatment of brain diseases in which neuroinflammation is involved.

Chronic valproic acid administration impairs contextual memory and dysregulates hippocampal GSK-3ß in rats.

Valproic acid (VPA), a long-standing anti-epileptic and anti-manic drug, exerts multiple actions in the nervous system through various molecular mechanisms. Neuroprotective properties have been attributed to VPA in different models of neurodegeneration, but contrasting results on its improvement of learning and memory have been reported in non-pathologic conditions. In the present study, we have tested on a hippocampal-dependent learning test, the contextual fear conditioning, the effect of chronic VPA administration through alimentary supplementation that allows relatively steady concentrations to be reached by a drug otherwise very rapidly eliminated in rodents. Contextual fear memory was significantly impaired in rats chronically treated with VPA for 4 weeks. To understand the cellular and molecular correlates of this amnesic effect with particular regard to hippocampus, we addressed three putatively memory-related targets of VPA action in this brain area, obtaining the following main results: i) chronic VPA promoted an increase of post-translational modifications of histone H3 (acetylation and phosphorylation) known to favor gene transcription; ii) adult neurogenesis in the dentate gyrus, which has been controversially reported to be affected by VPA, was unchanged; and iii) GSK-3ß, a kinase playing a key role in hippocampal plasticity, as well as in learning and memory, was dysregulated by VPA treatment. These results point at GSK-3ß dysregulation in the hippocampus as an important parameter in the amnesic effect of VPA. The VPA amnesic effect in the animal model here reported is also supported by some observations in patients and, therefore, it should be taken into account and monitored in VPA-based therapies.

Copper-zinc superoxide dismutase (SOD1) is released by microglial cells and confers neuroprotection against 6-OHDA neurotoxicity.

Microglial-neuronal interactions are essential for brain physiopathology. In this framework, recent data have changed the concept of microglia from essentially macrophagic cells to crucial elements in maintaining neuronal homeostasis and function through the release of neuroprotective molecules. Using proteomic analysis, here we identify copper-zinc superoxide dismutase (SOD1) as a protein produced and released by cultured rat primary microglia. Evidence for a neuroprotective role of microglia-derived SOD1 resulted from experiments in which primary cerebellar granule neurons (CGNs) were exposed to the dopaminergic toxin 6-hydroxydopamine (6-OHDA). Microglial conditioned medium, in which SOD1 had accumulated, protected CGNs from degeneration, and neuroprotection was abrogated by SOD1 inhibitors. These effects were replicated when exogenous SOD1 was added to a nonconditioned medium. SOD1 neuroprotective action was mediated by increased cell calcium from an external source. Further experiments demonstrated the specificity of SOD1 neuroprotection against 6-OHDA compared to other types of neurotoxic challenges. SOD1, constitutively produced and released by microglia through a lysosomal secretory pathway, is identified here for the first time as an essential component of neuroprotection mediated by microglia. This novel information is relevant to stimulating further studies of microglia-mediated neuroprotection in in vivo models of neurodegenerative diseases.