Cytosolic proliferating cell nuclear antigen (PCNA) orchestrates neutrophil hyperactivation in COVID-19

Neutrophils are central mediators of the hyperinflammatory response in severe SARS-CoV-2 infection. We report elevated cytosolic levels of proliferating cell nuclear antigen (PCNA) in neutrophils from patients with severe and critical COVID-19, correlating with enhanced NADPH oxidase-dependent reactive oxygen species (ROS) generation and neutrophil extracellular trap (NET) formation. Using T2AA, a small-molecule inhibitor of the PCNA scaffold, we demonstrate potent suppression of NADPH oxidase activation and NET release, particularly in response to SARS-CoV-2 RNA. Mechanistically, we identify a previously unrecognized interaction between PCNA and the heterodimeric S100A8/S100A9 (calprotectin), predominantly enriched in CD16<sup>high</sup>CD62L<sup>low</sup> neutrophils expanded during COVID-19. PCNA binds the dimeric S100A8/S100A9 complex mediated via S100A8 subunit with micromolar affinity, and this interaction is abrogated by tetramerization, suggesting regulation by intracellular calcium. Disruption of this complex by T2AA inhibited ROS production in an S100A8/S100A9-dependent manner, implicating calprotectin as a functional regulator of neutrophil activation. In a betacoronavirus mouse model, T2AA treatment attenuated lung inflammation, reduced NET and calprotectin levels, and shifted pulmonary neutrophils away from hyperactivated and immunosuppressive phenotypes, consistent with immune reprogramming toward resolution. These findings establish cytosolic PCNA as a central scaffold in neutrophil hyperactivation during COVID-19 and highlight its pharmacological disruption as a promising host-directed strategy to limit inflammation and prevent organ damage.

Authors

Institutions

Publication Details

Journal
Proceedings of the National Academy of Sciences
Published
2025-10-21
DOI
https://doi.org/10.1073/pnas.2503667122
Primary Topic
Neutrophil, Myeloperoxidase and Oxidative Mechanisms
Type
article
Field-Weighted Citation Impact
0.00
Controls
|||
ALL TIME
JAN
FEB
MAR
APR
MAY
JUN
JUL
AUG
SEP
OCT
article

Cytosolic proliferating cell nuclear antigen (PCNA) orchestrates neutrophil hyperactivation in COVID-19

Shída Yousefi, Lisa Krafft, Márick Rodrigues Starick, José C. Alves‐Filho et al.
Proceedings of the National Academy of Sciences
Neutrophil, Myeloperoxidase and Oxidative Mechanisms
article

Cytosolic proliferating cell nuclear antigen (PCNA) orchestrates neutrophil hyperactivation in COVID-19

Shída Yousefi, Lisa Krafft, Márick Rodrigues Starick, José C. Alves‐Filho, Marco A. Cassatella, Laura Tiberio, Théo Dhôte, Giovanni Saraceni-Tasso, Souganya Many, Lucie Pesenti, Natália Ribeiro Cabacinha Nóbrega, Rodrigo de Oliveira Formiga, Cícero José Luíz dos Ramos Almeida, Celso Martins Queiroz‐Junior, Mauro Martins Teixeira, Sylvie Chollet-Martin, Véronique Witko‐Sarsat, Muriel Andrieu, Thomas Vogl, Sabine Bailly, Anne Hosmalin, Frédéric Pène, Hans‐Uwe Simon, Fernando Spiller, Fernando Q. Cunha, Viviane Lima Batista, Vaarany Karunanithy, Daniela Bosisio, Nicola Tamassia, Margarita Hurtado-Nédelec, Anderson dos Santos Ramos, Clémence Martin, Philippe Frachet, Edroaldo Lummertz da Rocha, Vanessa Granger, Emilia Puig Lombardi, Darko Stojkov, Vivian Vasconcelos Costa, Pierre‐Régis Burgel, Luc de Chaisemartin, Maha Zohra Ladjemi, Luc Mouthon, Matheus Rodrigues Gonçalves, Manon Castel, Christophe Rousseau, François Chable de la Héronnière
article en

Abstract

Neutrophils are central mediators of the hyperinflammatory response in severe SARS-CoV-2 infection. We report elevated cytosolic levels of proliferating cell nuclear antigen (PCNA) in neutrophils from patients with severe and critical COVID-19, correlating with enhanced NADPH oxidase-dependent reactive oxygen species (ROS) generation and neutrophil extracellular trap (NET) formation. Using T2AA, a small-molecule inhibitor of the PCNA scaffold, we demonstrate potent suppression of NADPH oxidase activation and NET release, particularly in response to SARS-CoV-2 RNA. Mechanistically, we identify a previously unrecognized interaction between PCNA and the heterodimeric S100A8/S100A9 (calprotectin), predominantly enriched in CD16<sup>high</sup>CD62L<sup>low</sup> neutrophils expanded during COVID-19. PCNA binds the dimeric S100A8/S100A9 complex mediated via S100A8 subunit with micromolar affinity, and this interaction is abrogated by tetramerization, suggesting regulation by intracellular calcium. Disruption of this complex by T2AA inhibited ROS production in an S100A8/S100A9-dependent manner, implicating calprotectin as a functional regulator of neutrophil activation. In a betacoronavirus mouse model, T2AA treatment attenuated lung inflammation, reduced NET and calprotectin levels, and shifted pulmonary neutrophils away from hyperactivated and immunosuppressive phenotypes, consistent with immune reprogramming toward resolution. These findings establish cytosolic PCNA as a central scaffold in neutrophil hyperactivation during COVID-19 and highlight its pharmacological disruption as a promising host-directed strategy to limit inflammation and prevent organ damage.

Proceedings of the National Academy of SciencesVol. 122(43)
Universidade Federal de Minas Gerais (BR), University of Bern (CH), University of Verona (IT), Centre National de la Recherche Scientifique (FR), Instituto Federal de Educação, Ciência e Tecnologia de Minas Gerais (BR), Inserm (FR), Universidade de São Paulo (BR), Université Paris Cité (FR), University of Münster (DE), Brescia University (US), Universidade Federal de Santa Catarina (BR), Sorbonne Paris Cité (FR), Hôpital Cochin (FR), Assistance Publique – Hôpitaux de Paris (FR), Hôpitaux Universitaires Paris-Ouest (FR), Institute of Immunology (HR), Institut Cochin (FR), Medizinische Hochschule Brandenburg Theodor Fontane (DE), Institut de Biologie Structurale (FR), Universitätsklinikum Brandenburg an der Havel (DE), Institut des Maladies Génétiques Imagine (FR), Institute of Pharmacology (CZ), University of Brescia (IT), Université Grenoble Alpes (FR)
Openalex Percentile: Top 69%
Neutrophil, Myeloperoxidase and Oxidative Mechanisms
DOIOpen Access PDFOpenAlex
AI Navigator

Ask Laika to Summarize, Analyze, and Connect papers live on the map.

Summarize Papers & Methodologies

Extract key findings, datasets, and comparative methods across publications.

Benchmark Rankings & Visual Analytics

Rank top research institutions, authors, funders, topics, and journals by Field-Weighted Citation Impact (FWCI) and paper volume with instant charts.

Connect Distant Disciplines

Bridge topological clusters on the map to find hidden collaborative intersections.