RationaleViral-induced exacerbation of asthma remain a major cause of hospitalization and mortality. New human relevant models of the airways are urgently needed to understand how respiratory infections may trigger asthma attacks, and to advance treatment development.ObjectivesTo develop a new human relevant model of rhinovirus-induced asthma exacerbation that recapitulates viral infection of asthmatic airway epithelium, neutrophil transepithelial migration, and enables evaluation of immunomodulatory therapy.MethodsA micro-engineered model of fully differentiated human mucociliary airway epithelium was stimulated with IL-13 to induce a Th2-type asthmatic phenotype and infected with live human rhinovirus 16 (HRV16) to reproduce key features of viral-induced asthma exacerbation.Measurements and Main ResultsInfection with HRV16 replicated key hallmarks of the cytopathology and inflammatory responses observed in human airways. Generation of a Th2 microenvironment through exogenous IL-13 stimulation induced features of asthmatics airways, including goblet cell hyperplasia, reduction of cilia beating frequency, and endothelial activation, but did not alter rhinovirus infectivity or replication. High resolution kinetic analysis of secreted inflammatory markers revealed that IL-13 treatment altered the IL-6, IFN-λ1, and CXCL10 secretion in response to HRV16. Neutrophil transepithelial migration was greatest when viral infection was combined with IL-13 treatment, while treatment with MK-7123, a CXCR2 antagonist, reduced neutrophil diapedesis in all conditions.ConclusionsThis micro-engineered Airway Lung-Chip provides a novel human-relevant platform for exploring the complex mechanisms underlying viral-induced asthma exacerbation. Our data suggest that IL-13 may impair the hosts’ ability to mount an appropriate and coordinated immune response to rhinovirus infection. We also show that the Airway Lung-Chip can be used to assess the efficacy of modulators of the immune response.NoteEmulate®, Human Emulation System®, S-1™, ER-1™, and ER-2™ are trademarks of Emulate, Inc., and any other trademarks used herein remain with their respective holders. The technology disclosed in this document may be covered by one or more patents or patent applications, and no license to these is granted herein. You are solely responsible for determining whether you have all intellectual property rights that are necessary for your intended use of any of the disclosed materials, and whether you are required to obtain any additional intellectual property rights from a third party. Further information is available by contacting the authors.At a Glance CommentaryScientific Knowledge on the SubjectNew therapies for asthma exacerbations remain a significant unmet medical need. Development of human relevant preclinical models are needed to further elucidate the complex mechanisms underlying asthma exacerbation and investigate new therapeutic strategies.What This Study Adds to the FieldUsing a human Airway Lung-Chip model, we show here for the first time a live human rhinovirus (HRV) infection of the asthmatic epithelium that recapitulates complex features of viral-induced asthma exacerbation. The dynamic microenvironment of the chip enables the real-time study of virus infection, epithelial response, and immune cell recruitment under healthy and asthmatic conditions. The model reproduces key endpoints that have been observed in asthmatics and individuals infected with rhinovirus including the ciliated cell sloughing, altered cilia beating frequency, goblet cell hyperplasia, increased expression of adhesion molecules in microvascular endothelial cells, and inflammatory mediator release. High-resolution temporal analysis of secreted inflammatory markers enabled by dynamic sampling revealed alteration of IL-6, IFN-λ1 and CXCL10 secretory phases after rhinovirus infection in an IL-13 high environment. Leveraging high-content imaging and analysis of circulating inflammatory cells, we demonstrated the efficacy of a CXCR2 antagonist to reduce adhesion, motility, and transmigration of perfused human neutrophils. Thus, this micro-engineered chip may offer a powerful addition to preclinical models for understanding mechanisms underlying asthma exacerbation pathology and developing new therapeutic strategies.
