“Long COVID” affects approximately 60 million people worldwide, and a common manifestation is post-COVID-19 Pulmonary Fibrosis (PC19PF). PC19PF can cause ongoing shortness of breath, due to long lasting lung scarring that makes it harder for the lungs to expand and take in oxygen. Very little is currently understood about the mechanisms that cause PC19PF. The goal of my research is to develop a stem-cell derived model to study post-viral pulmonary fibrosis. This model will provide a powerful platform to uncover disease mechanisms and accelerate the development and testing of novel therapeutic options to treat those with PC19PF.
Impact
“Long COVID” affects around 60 million people worldwide, and post-COVID-19 pulmonary fibrosis (PC19PF) is one of its most debilitating outcomes, causing lasting lung scarring and breathlessness. With current drugs proving ineffective and little known about the disease mechanisms, new models are urgently needed. By developing a stem cell–derived system to study PC19PF, this research will accelerate the discovery of targeted therapies. Beyond the scope of PC19PF, our experimental model can also be widely applicable to other alveolar diseases, such as COPD and idiopathic pulmonary fibrosis.
reNEW research
We have developed a protocol to combine induced pluripotent stem cell (iPSC)-derived type 2 alveolar epithelial cells, macrophages and lung mesenchyme in an air-liquid interface platform. We have determined the optimal media conditions and the assessed the viability of these tri-cultures over extended periods of time via immunofluorescence and flow cytometry. To test the system, we have introduced pro-fibrotic agents, such as exogenous TGF-β and bleomycin, and measured key fibrotic genes post-treatment using qRT-PCR. When infected with SARS-CoV-2, tri-cultures exhibit continuous waves of viral shedding, with altered antiviral and fibrotic gene expression compared with type 2 alveolar epithelial cells alone. Future directions will use histology to quantify fibrosis, and use scRNA-seq to determine communication networks between the alveolar epithelium, mesenchyme and macrophages during SARS-CoV-2 infection.
Image description
This image is a tri-culture of iPSC-derived type 2 alveolar epithelial cells, lung mesenchyme and macrophages infected with SARS-CoV-2. In this stain, iPSC-derived type 2 alveolar epithelial cells (red) and SARS-CoV-2 viral foci (green) are visible. These foci likely serve as sources of ongoing viral shedding, leading to the infection of neighboring epithelial cells within the alveoli.
Credits
Jack Murphy, Honours Student, Werder Lab, reNEW Melbourne.
Matt Gartner, Research officer, Kanta Sabbarao, The Peter Doherty Institute for Infection and Immunity.
