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Bhakta, I. N.

Publications and source records attributed to Bhakta, I. N..

2 recordsLinked to original sources

Fluidic Programmable Gravi-maze Array for High Throughput Multiorgan Drug Testing

The high attrition rate of drug candidates in clinical trials underscores the urgent need for more predictive preclinical models that accurately replicate human physiology. Traditional 2D cell cultures and animal models often fail to predict human responses due to their limited physiological relevance, particularly for biologics and immunotherapies involving complex multicellular and cross-organ interactions. This highlights the need for modeling and measurements of multiorgan interactions at higher throughput, prompting the development of multiorgan-on-a-plate platforms. Here, we present OrganRX, a modular, gravity-driven recirculation-based platform designed to imitate human organ function, physiological flow, immune cells circulation, and inter-organ communication in vitro. The Fluidic Programmable Gravi-maze Array (FPGA) technology integrates multiple organ models, including gut, liver, kidney, brain, tumor, and vascular compartments, within a microfluidic architecture designed to reproduce physiologically relevant shear stresses and gravity-driven recirculating flow that facilitates inter-organ communication. Using computational fluid dynamics (CFD) simulations and impedance-based flow validation, we confirmed accurate shear control across organ compartments. Organ-specific and multiorgan models were constructed using 3D extracellular matrix hydrogels and assessed for metabolism, toxicity, and senescence. Liver-kidney co-cultures demonstrated metabolic interplay via differential albumin and urea production. In addition, the platform was evaluated for biologics testing using immune-oncology models incorporating tumor spheroids, endothelial barriers, and circulating immune cells. Antigen-specific T-cells, checkpoint inhibitors, bispecific antibody and antibody-drug conjugate (ADC) studies demonstrated the ability to measure on-target tumor killing, off-target toxicity, cytokine release, and bystander effects across interconnected tissue compartments under dynamic recirculating conditions. The system enabled longitudinal evaluation of immune-mediated cytotoxicity, tissue-selective responses, and cross-organ signaling not readily captured in conventional static assays. Overall, the OrganRX platform offers a physiologically relevant, scalable, and automation-compatible platform for preclinical drug evaluation, biologics safety assessment, and disease modeling. Its ability to capture complex, dynamic inter-organ effects position it as a powerful tool for advancing translational research, mechanistic toxicology, and precision medicine.

bioengineering↗

Dendrite injury, but not axon injury, triggers neuroprotection in Drosophila models of neurodegenerative disease.

Dendrite defects and loss are early cellular alterations observed across neurodegenerative diseases that play a role in early disease pathogenesis. Dendrite degeneration can be modeled by expressing pathogenic polyglutamine disease transgenes in Drosophila neurons in vivo. Here, we show that we can protect against dendrite loss in neurons modeling neurodegenerative polyglutamine diseases through injury to a single primary dendrite branch. We find that this neuroprotection is specific to injury-induced activation of dendrite regeneration: neither injury to the axon nor injury just to surrounding tissues induces this response. We show that the mechanism of this regenerative response is stabilization of the actin (but not microtubule) cytoskeleton. We also demonstrate that this regenerative response may extend to other neurodegenerative diseases. Together, we provide evidence that activating dendrite regeneration pathways has the potential to slow-or even reverse-dendrite loss in neurodegenerative disease.

neuroscience↗