Microfluidic device for recapitulating PAH-afflicted pulmonary artery: design, fabrication, and on-chip cell culture

Abstract

Abstract Pulmonary arterial hypertension (PAH), a rare condition and a hyperproliferative vascular disorder, is characterized by vascular remodeling of the intrapulmonary arterial wall, resulting in elevated pulmonary vascular resistance, right ventricular hypertrophy, and eventually right heart failure and death. Although animal models can reproduce the chief feature of the disease, i.e., elevated pulmonary arterial pressure, they do not accurately portray the biology of human PAH. Further, the FDA Modernization Act 2021 encourages using alternatives to animal models such as organ chip models in non-clinical studies because the latter models are not only humane but also expected to expedite drug development and discovery. As such, we recently established the feasibility of designing, developing, and deploying a PAH-on-a-chip for studying PAH pathophysiology and screening for anti-PAH drugs in our laboratory. This PAH-chip model mimics five layers of the pulmonary artery and allows the growing of adult PAH cells in separate channels, facilitating cell-cell and cell-matrix interactions. Importantly, the device can reconstruct the major clinical features of PAH, including arterial muscularization and plexiform lesions. Here, we described a step-by-step detailed method of PAH-chip design and fabrication and cell seeding on the device so that any biologist can prepare the device and study PAH pathophysiology in a laboratory setting. Our protocol is different from other published methods of PDMS-based chips in terms of application of the device and the depth of the details. We envision that this method of chip fabrication can also be used to study other pulmonary vascular disorders.