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bioRxiv · 10.1101/2023.07.14.548971

Deep spatial proteomic exploration of severe COVID-19-related pulmonary injury in post-mortem specimens

Abstract

The lung, as a primary target of SARS-CoV-2, exhibits heterogeneous microenvironment accompanied by various histopathological changes following virus infection. However, comprehensive insight into the protein basis of COVID-19-related pulmonary injury with spatial resolution is currently deficient. Here, we generated a region-resolved quantitative proteomic atlas of seven major pathological structures within the lungs of COVID-19 victims by integrating histological examination, laser microdissection, and ultrasensitive proteomic technologies. Over 10,000 proteins were quantified across 71 dissected FFPE post-mortem specimens. By comparison with control samples, we identified a spectrum of COVID-19-induced protein and pathway dysregulations in alveolar epithelium, bronchial epithelium, and pulmonary blood vessels, providing evidence for the proliferation of transitional-state pneumocytes. Additionally, we profiled the region-specific proteomes of hallmark COVID-19 pulmonary injuries, including bronchiole mucus plug, pulmonary fibrosis, airspace inflammation, and hyperplastic alveolar type 2 cells. Bioinformatic analysis revealed the enrichment of cell-type and functional markers in these regions (e.g. enriched TGFBI in fibrotic region). Furthermore, we identified the up-regulation of proteins associated with viral entry, host restriction, and inflammatory response in COVID-19 lungs, such as FURIN and HGF. Collectively, this study provides spatial proteomic insights for understanding COVID-19-caused pulmonary injury, and may serve as a valuable reference for improving therapeutic intervention for severe pneumonia.

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BibTeXRIS

Mao, Y., Chen, Y., Li, Y., Ma, L., Wang, X., Wang, Q., He, A., Liu, X., Dong, T., Gao, W., Xu, Y., Liu, L., Ren, L., Liu, Q., Zhou, P., Hu, B., Zhou, Y., Tian, R., Shi, Z.-L.. 2023-07-17. Deep spatial proteomic exploration of severe COVID-19-related pulmonary injury in post-mortem specimens. https://doi.org/10.1101/2023.07.14.548971

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