Biology subjects

Bolognin, S.

Publications and source records attributed to Bolognin, S..

8 recordsLinked to original sources

bioRxiv2026

Lab-on-a-chip device integrating a human stem cell-based blood-brain barrier model with neural organoids for translational research

For advanced biomedical research, complex, well-described human blood-brain barrier (BBB) models are crucial for studying central nervous system pathologies and brain targeting of nanotherapeutics. Our aim was to establish and characterize a complex lab-on-a-chip (LOC) system integrating a BBB model with neural organoids (NO). We optimized the conditions for BBB-NO models under static and dynamic circumstances. The combination of a human stem cell-derived BBB co-culture model with human midbrain organoids in a microfluidic LOC allowed the observation of BBB and neural tissue changes and the separate analysis of the barrier and brain units. The LOC design enabled phase contrast and fluorescent microscopy on the whole brain endothelial culture surface, barrier integrity and permeability measurements across the BBB model, and molecule passage into NOs. BBB-specific endothelial morphology, gene and protein expression, and good barrier integrity were demonstrated, corroborating the strength of the LOC engineering and cellular design. The transport of targeted nanoparticles across the BBB model followed by their entry to neural organoids validated the barrier integrity and transporter functionality of the dynamic integrated complex model. As a proof-of-concept experiment to confirm the translational value of the BBB-NO model integrated in the LOC device, we examined a clinically used hyperosmolar iodinated contrast agent, iopamidol, with confirmed neurological side effects. We corroborated that iopamidol induces transient BBB dysfunction and neural effects in the complex system, not only validating the complex dynamic BBB-NO model but also pointing to the necessity to study BBB changes together with NO functions.

cell biology↗

bioRxiv2026

Replicative senescence of neural progenitors induces astrocyte senescence in 2D cultures and human midbrain organoids

Astrocyte senescence (astrosenescence) has emerged as a potential mechanism through which ageing may progressively impair glial homeostatic neuronal support and render the brain more vulnerable to neurodegenerative diseases such as Parkinsons disease (PD). Yet human experimental models that specifically recapitulate astrosenescence within a PD-relevant genetic background are lacking. Here, we applied passage-induced replicative exhaustion to human iPSC-derived neuroepithelial stem cells (NESCs) from a healthy donor and LRRK2-G2019S PD patients to establish an in vitro midbrain ageing model. Extended passaging induced senescence-associated changes in NESCs, including reduced proliferative capacity, decreased cleaved caspase 3 (CC3) and telomerase mRNA expression, and DNA damage response (DDR) activation, while preserving differentiation potential. Astrocytes derived from aged progenitors showed an increase in SA-{beta}-gal activity, loss of Lamin B1, DDR activation, and an altered mitochondrial morphology. In human midbrain organoids (hMOs), passage-induced ageing was associated with astrocyte-specific DDR activation and lipidomic remodelling. A multi-modal integrative analysis further revealed that, despite the variable penetrance of individual senescence-associated markers across lines, passage condition constitutes the primary discriminant of the collective cellular state, supporting the view that replicative senescence as a biological program is detectable only when individual readouts are aggregated across modalities. Together, this work establishes a human iPSC-based platform recapitulating key features of cellular senescence in both healthy and LRRK2-G2019S contexts and provides an in vitro platform to investigate the contribution of astrosenescence to PD-related neurodegeneration.

neuroscience↗

bioRxiv2022

Development of a multi-sensor integrated midbrain organoid-on-a-chip platform for studying Parkinson's disease

Due to its ability to recapitulate key pathological processes in vitro, midbrain organoid technology has significantly advanced the modeling of Parkinsons disease over the last few years. However, some limitations such as insufficient tissue differentiation and maturation, deficient nutrient supply, and low analytical accessibility persist, altogether restricting the technology from reaching its full potential. To overcome these drawbacks, we have developed a multi-sensor integrated organ-on-a-chip platform capable of monitoring the electrophysiological, respiratory, and dopaminergic activity of human midbrain organoids. Our study showed that microfluidic cultivation resulted in a marked reduction in necrotic core formation, improved tissue differentiation as well as the recapitulation of key pathological hallmarks. Non-invasive monitoring employing an orthogonal sensing strategy revealed a clear time dependency in the onset of Parkinsons disease-related phenotypes, reflecting the complex progression of the neurodegenerative disorder. Furthermore, drug-mediated rescue effects were observed after treatment with the repurposed compound 2-hydroxypropyl {beta}-cyclodextrin, highlighting the platforms potential in the context of drug screening applications as well as personalized medicine.

bioengineering↗

bioRxiv2019

Cultivation and characterization of human midbrain organoids in sensor integrated microfluidic chips

1.With its ability to emulate microarchitectures and functional characteristics of native organs in vitro, induced pluripotent stem cell (iPSC) technology has enabled the generation of a plethora of organotypic constructs, including that of the human midbrain. However, reproducibly engineering and differentiating such human midbrain organoids (hMOs) under a biomimetic environment favorable for brain development still remains challenging. This study sets out to address this problem by combining the potential of iPSC technology with the advantages of microfluidics, namely its precise control over fluid flow combined with sensor integration. Here, we present a novel sensor-integrated platform for the long-term cultivation and non-invasive monitoring of hMOs under an interstitial flow regime. Our results show that dynamic cultivation of iPSC-derived hMOs maintains high cellular viabilities and dopaminergic neuron differentiation over prolonged cultivation periods of up to 50 days.

bioengineering↗

bioRxiv2019

Parkinson’s disease phenotypes in patient specific brain organoids are improved by HP-β-CD treatment

The etiology of Parkinsons disease (PD) is only partially understood despite the fact that environmental causes, risk factors, and specific gene mutations are contributors to the disease. Biallelic mutations in the PTEN-induced putative kinase 1 (PINK1) gene involved in mitochondrial homeostasis, vesicle trafficking, and autophagy, are sufficient to cause PD. By comparing PD patient-derived cells, we show differences in their energetic profile, imbalanced proliferation, apoptosis, mitophagy, and a reduced differentiation efficiency to dopaminergic neurons compared to control cells. Using CRISPR/Cas9 gene editing, correction of a patients point mutation ameliorated the metabolic properties and neuronal firing rates but without reversing the differentiation phenotype. However, treatment with 2-Hydroxypropyl-{beta}-Cyclodextrin (HP-{beta}-CD) increased the mitophagy capacity of neurons leading to an improved dopaminergic differentiation of patient specific neurons in midbrain organoids. In conclusion, we show that treatment with a repurposed compound is sufficient for restoring dopaminergic differentiation of PD patient-derived cells.

neuroscience↗

bioRxiv2019

Machine learning-assisted neurotoxicity prediction in human midbrain organoids

A major challenge in the field of neurodegenerative diseases is the poor translation of pre-clinical models to clinical applications. The human brain is an immensely complex structure, which makes it difficult to recapitulate its development, function and disorders. In the recent years, brain organoids derived from human induced pluripotent stem cells have risen as novel tools to study neurodegenerative diseases such as Parkinsons disease (PD). PD is a multifactorial disorder, with aging, genetics and environmental factors as key etiological elements. The majority of the PD cases are idiopathic and proposed to result from a complex interaction between genetic predisposition and environmental exposure. Consequently, the identification of potentially disease causing environmental factors is of critical importance. Organoids, as complex multi-cellular tissue proxies, are an ideal tool to study cellular response to environmental changes. However, with increasing complexity of the system, usage of quantitative tools becomes challenging. This led us to develop an automated high-content image analysis pipeline for image-based cell profiling in the organoid system. Here, we introduce a midbrain organoid system that recapitulates features of neurotoxin-induced PD, representing a platform for machine-learning-assisted prediction of neurotoxicity in high-content imaging data. This model is a valuable tool for advanced in vitro PD modeling and for the screening of putative neurotoxic compounds.

pharmacology and toxicology↗

bioRxiv2019

Single-cell transcriptomics reveals multiple neuronal cell types in human midbrain-specific organoids

Human stem cell-derived organoids have great potential for modelling physiological and pathological processes. They recapitulate in vitro the organisation and function of a respective organ or part of an organ. Human midbrain organoids (hMOs) have been described to contain midbrain-specific dopaminergic neurons that release the neurotransmitter dopamine. However, the human midbrain contains also additional neuronal cell types, which are functionally interacting with each other. Here, we analysed hMOs at high-resolution by means of single-cell RNA-sequencing (scRNA-seq), imaging and electrophysiology to unravel cell heterogeneity. Our findings demonstrate that hMOs show essential neuronal functional properties as spontaneous electrophysiological activity of different neuronal subtypes, including dopaminergic, GABAergic, and glutamatergic neurons. Recapitulating these in vivo features makes hMOs an excellent tool for in vitro disease phenotyping and drug discovery.

neuroscience↗

bioRxiv2017

In Vivo Phenotyping Of Parkinson-Specific Stem Cells Reveals Increased a-Synuclein Levels But No Spreading

Parkinson's disease is a progressive age-associated neurological disorder. One of the major neuropathological hallmarks of Parkinsons disease is the appearance of protein aggregates, mainly consisting of the protein alpha-Synuclein. These aggregates have been described both in genetic as well as idiopathic forms of the disease. Currently, Parkinsons disease patient-specific induced pluripotent stem cells (iPSCs) are mainly used for in vitro disease modeling or for experimental cell replacement approaches. Here, we demonstrate that these cells can be used for in vivo disease modeling. We show that Parkinsons disease patient-specific, iPSC-derived neurons carrying the LRRK2-G2019S mutation show an upregulation of alpha-Synuclein after transplantation in the mouse brain. However, further investigations indicate that the increased human alpha-Synuclein levels fail to induce spreading or aggregation in the mouse brain. We therefore conclude that grafting of these cells into the mouse brain is suitable for cell autonomous in vivo disease modeling but has strong limitations beyond that. Furthermore, our results support the hypothesis that there might be a species barrier between human to mouse concerning alpha-Synuclein spreading.

neuroscience↗