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Hinojosa, C. D.

Publications and source records attributed to Hinojosa, C. D..

3 recordsLinked to original sources

A Microengineered Brain-Chip to Model Neuroinflammation in Humans

Species differences in the brain and the blood-brain barrier (BBB) biology hamper the translation from animal models to humans and impede the development of specific therapeutics for brain diseases. Here we present a human Brain-Chip engineered to recapitulate critical aspects of the complex brain cell-cell interactions that mediate neuroinflammation development. Our human organotypic microphysiological system (MPS) includes endothelial-like cells, pericytes, glia, and cortical neurons and maintains BBB permeability at in vivo relevant levels, providing a significant improvement in complexity and clinical mimicry compared to previous MPS models. This is the first report of a Brain-Chip with an RNA expression profile close to that of the adult human cortex and that demonstrates advantages over Transwell culture. Through perfusion of TNF-, we recreated key inflammatory features, such as glia activation, the release of proinflammatory cytokines, and increased barrier permeability. Our model may provide a reliable tool for mechanistic studies in neuron-glial interactions and dysregulation of BBB function during neuroinflammation.

bioengineering↗

A novel Organ-Chip system emulates three-dimensional architecture of the human epithelia and allows fine control of mechanical forces acting on it.

Successful translation of in vivo experimental data to human patients is an unmet need and a bottleneck in the development of effective therapeutics. micro technology aims to address this need with significant advancements reported recently that enable modeling of organ level function. These microengineered chips enable researcher to recreate critical elements such as in vivo relevant tissue-tissue interface, air-liquid interface, and mechanical forces, such as mechanical stretch and fluidic shear stress, are crucial in emulating tissue level functions. Here, we present the development of a new, comprehensive 3D cell-culture system, where we combined our proprietary Organ-Chip technology with recent advantages in three-dimensional organotypic culture. Leveraging microfabrication techniques, we engineered a flexible chip that consists of a channel containing an organotypic epithelium surrounded by two vacuum channels that can be actuated to stretch the hydrogel throughout its thickness. Furthermore, the ceiling of this channel is a removable lid with a built-in microchannel that can be perfused with liquid or air and removed as needed for direct access to the tissue. The floor of this channel is a porous flexible membrane in contact with a microfluidic channel that provides diffusive mass transport to and from the channel. This additional microfluidic channel can be coated with endothelial cells to emulate a blood vessel and capture endothelial interactions. Our results show that the Open-Top Chip design successfully addresses common challenges associated with the Organs-on-Chips technology, including the capability to incorporate a tissue-specific extracellular matrix gel seeded with primary stromal cells, to reproduce the architectural complexity of tissues by micropatterning the gel, that can be extracted for H&E staining. We provide proof-of-concept data on the feasibility of the system using skin and alveolar epithelial primary cells and by simulating alveolar inflammation.

bioengineering↗

Modeling Alpha-Synuclein Pathology in a Human Brain-Chip to Assess Blood-Brain Barrier Disruption in Parkinson's Disease

Parkinsons disease and related synucleinopathies are characterized by the abnormal accumulation of alpha-synuclein aggregates, loss of dopaminergic neurons, and gliosis in the substantia nigra. Although clinical evidence and in vitro studies indicate disruption of the Blood-Brain Barrier in Parkinsons disease, the mechanisms mediating the endothelial dysfunction remain elusive. Lack of relevant models able to recapitulate the order of events driving the development of the disease in humans has been a significant bottleneck in the identification of specific successful druggable targets. Here we leveraged the Organs-on-Chips technology to engineer a human Brain-Chip representative of the substantia nigra area of the brain containing dopaminergic neurons, astrocytes, microglia, pericytes, and microvascular brain endothelial cells, cultured under fluid flow. Our Syn fibril-induced model was capable of reproducing several key aspects of Parkinsons disease, including accumulation of phosphorylated Syn (pSer129-Syn), mitochondrial impairment, neuroinflammation, and compromised barrier function. This model is poised to enable research into the dynamics of cell-cell interactions in human synucleinopathies and to serve as testing platform for novel therapeutic interventions, including target identification and target validation.

bioengineering↗