AccScience Publishing / IJB / Volume 12 / Issue 5 / DOI: 10.36922/IJB026320343
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RESEARCH ARTICLE

Bioprinting of a human neuron model for quantifying pollutant toxicity

Emmie Yao1† ,  Steven Chen2† ,  Grace Lu3 ,  Changyu Sun4 ,  Quyen T. Nguyen5*
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1 Department of Chemical and Nano Engineering, University of California San Diego, La Jolla, California , United States of America
2 Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, California , United States of America
3 Global Health Program, University of California San Diego, La Jolla, California , United States of America
4 School of Biological Sciences, University of California San Diego, La Jolla, California , United States of America
5 Departments of Otolaryngology-Head and Neck Surgery & Pharmacology, University of California San Diego, La Jolla, California , United States of America
†These authors contributed equally to this work.
IJB 2026, 12(5), 026320343 https://doi.org/10.36922/IJB026320343
Received: 6 August 2026 | Revised: 8 September 2026 | Accepted: 9 September 2026 | Published online: 10 September 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Abstract

Although pesticides are widely used in modern agriculture, growing evidence indicates that chronic exposure to these environmental contaminants contributes to the development of neurodegenerative disorders. This concern is amplified by the global rise in aging populations and the corresponding increase incidence in neurodegenerative diseases. Among the most widely used pesticides, organophosphates, particularly chlorpyrifos (CPF), are of significant concern due to their extensive agricultural use and well-established neurotoxic effects. Here, we present a 3-dimensional (3D) human neuron progenitor cell (hNPC) tissue model, fabricated using digital light processing (DLP)-based bioprinting. This platform enables precise spatial control over the cell density, geometry, and mechanical properties within a gelatin methacrylate (GelMA) scaffold, providing a tunable and biomimetic extracellular matrix. Using this system, we evaluated hNPC response to CPF exposure within a physiologically relevant 3D context. We further investigated CPF-induced neurotoxicity, specifically exploring acetylcholinesterase gene expression as a primary mechanistic etiology. Our findings demonstrate that our engineered 3D bioprinted constructs offer a more physiologically relevant and cost-effective platform for studying pollutant-induced neurotoxicity compared to conventional 2-D and in vivo rodent models, respectively. This work establishes a scalable 3D bioprinted system for mechanistic toxicology studies and advances predictive modeling of human neurological responses to environmental toxicants.

Keywords
Bioprinting
Human neuron tissue model
Pollutants
Toxicity
Chlorpyrifos
Funding
Emmie Yao is supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1650112.
Conflict of interest
The authors declare no competing interests.
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International Journal of Bioprinting, Electronic ISSN: 2424-8002 Print ISSN: 2424-7723, Published by AccScience Publishing