Human Lung Small Airway-on-a-Chip Protocol

Abstract

Organs-on-chips are microfluidic cell culture devices created using microchip manufacturing techniques that contain hollow microchannels lined by living cells, which recreate specialized tissue-tissue interfaces, physical microenvironments, and vascular perfusion necessary to recapitulate organ-level physiology in vitro. Here we describe a protocol for fabrication, culture, and operation of a human lung "small airway-on-a-chip," which contains a differentiated, mucociliary bronchiolar epithelium exposed to air and an underlying microvascular endothelium that experiences fluid flow. First, microengineering is used to fabricate a multilayered microfluidic device that contains two parallel elastomeric microchannels separated by a thin rigid porous membrane; this requires less than 1 day to complete. Next, primary human airway bronchiolar epithelial cells isolated from healthy normal donors or patients with respiratory disease are cultured on the porous membrane within one microchannel while lung microvascular endothelial cells are cultured on the opposite side of the same membrane in the second channel to create a mucociliated epithelium-endothelium interface; this process take about 4-6 weeks to complete. Finally, culture medium containing neutrophils isolated from fresh whole human blood are flowed through the microvascular channel of the device to enable real-time analysis of capture and recruitment of circulating leukocytes by endothelium under physiological shear; this step requires less than 1 day to complete. The small airway-on-a-chip represents a new microfluidic tool to model complex and dynamic inflammatory responses of healthy and diseased lungs in vitro.

Toxicological evaluation of airborne particulate matter. Are cell culture technologies ready to replace animal testing?

“…Research and development in the area of lung‐on‐chip technology has recently been applied to drug screening (Benam et al, ; Skardal et al, ) and to the study of lung physiology (Benam et al, ; Henry et al, ; Humayun, Chow, & Young, ; J. D. Stucki et al, ) and pathophysiology (Huh et al, ; Jain et al, ), and we wonder whether this technology was also used in investigations related to environmental toxicology. However, although the technology is promising and does not have ethical and regulatory limitations, its use to study the response of human cells to ambient toxicants has not yet been presented in the literature (Cho & Yoon, ).…”

“…Research and development in the area of lung-on-chip technology has recently been applied to drug screening (Benam et al, 2016;Skardal et al, 2017) and to the study of lung physiology (Benam et al, 2017;Henry et al, 2017;Humayun, Chow, & Young, 2018;J. D. Stucki et al, 2018) and pathophysiology (Huh et al, 2012;Jain et al, 2018), and we wonder whether this technology was also used in investigations related to environmental toxicology.…”

Translating advances in organ‐on‐a‐chip technology for supporting organs

“…3A), alveolar-capillary interface 46,66 (Fig. 1A), small airway with dynamic inflammatory response capabilities, 29 multicompartmental system combining three critical brain barriers (blood-brain, braincerebrospinal fluid [CSF], and blood-CSF), 39 complex endothelialized myocardial structures, 47 bone with bone marrow, 27 as well as gut with flora and peristalsis. 36 Simpler models include constructs such as myocytes cultured on a film, 15 liver microtissues, 67 or hepatocyte spheroids and hepatocytes and hepatic stellate cells (HSCs) that were cocultured without direct cell-cell contact to investigate the interaction of HSCs.…”

“…The concept introduces a new line of clinical application of organ-on-a-chip technology for 46 and small airway. 29…”

Organ‐on‐chip models: Implications in drug discovery and clinical applications

“…Benam et al, 2017). This paper illustrates how to engineer a small airway, an air-blood barrier, for study of physiological and pathophysiological mechanisms-the parameters of which can be modulated based on the understanding of said disease in question.…”