Deciphering the nanobiophysics of virus-host interactions in 3D cellular systems

Projektinformationen

SingViroPhys

ID Finanzhilfevereinbarung: 101088316

DOI

10.3030/101088316

EK-Unterschriftsdatum 19 Juni 2023

Startdatum 1 Dezember 2023

Enddatum 30 November 2028

Finanziert unter

• European Research Council (ERC)

Gesamtkosten

€ 2 867 346,00

EU-Beitrag

€ 2 867 346,00

Koordiniert durch

UNIVERSITE CATHOLIQUE DE LOUVAIN
Belgium

Periodic Reporting for period 1 - SingViroPhys (Deciphering the nanobiophysics of virus-host interactions in 3D cellular systems)

Berichtszeitraum: 2023-12-01 bis 2026-05-31

Zusammenfassung vom Kontext und den Gesamtzielen des Projekts

Viruses remain one of the most serious threats to human health, a reality dramatically illustrated by recent global pandemics. Viral infection is initiated by a sequence of finely regulated events—viral landing on the cell surface, engagement with host receptors, and subsequent entry into the cell—that ultimately determine viral tropism, infectivity, and disease outcome. Despite decades of research, these very first steps of infection remain poorly understood at the molecular and mechanical levels. A major limitation comes from the experimental systems traditionally used to study virus–host interactions: most rely on 2D cancer-derived cell lines that fail to capture the structural complexity, polarity, and cell-to-cell heterogeneity of human epithelial tissues. As a result, crucial regulatory mechanisms occurring in realistic physiological environments remain unexplored.
This project proposes to overcome these limitations by establishing a new paradigm for investigating viral entry under near-physiological 3D conditions. By combining advanced nanobiophysical methods (single-virus atomic force microscopy (AFM) and optical tweezers), we aim to quantify, in real time, the molecular forces, dynamics, and mechanical checkpoints that govern the earliest stages of infection. Using epithelial models of increasing complexity, from monolayers to organoids and engineered tissues, we will decipher how tissue organization, differentiation, and heterogeneity influence the pathways through which viruses attach and penetrate host cells.
The overarching objective is to build an integrative and mechanistic picture of viral entry as it occurs in vivo, and to identify new physical and molecular vulnerabilities that could be exploited for antiviral intervention.

Arbeit, die ab Beginn des Projekts bis zum Ende des durch den Bericht erfassten Berichtszeitraums geleistet wurde, und die wichtigsten bis dahin erzielten Ergebnisse

A major milestone of the project has already been achieved: we successfully designed, built, and validated the first integrated platform combining AFM and optical tweezers for single-virus measurements. The coupling of these two high-precision techniques allows simultaneous mechanical manipulation, force quantification, and dynamic tracking of virus–cell interactions with a resolution previously unattainable. We demonstrated, for the first time, that this system enables the quantitative measurement of binding forces between individual viral particles and living cells, confirming its robustness, sensitivity, and suitability for studying early infection events.
In parallel, we established 3D epithelial culture systems and performed an in-depth characterization of how cells differentiate within these environments. Using molecular and imaging approaches, we showed that differentiation leads to significant remodeling of the cell surface landscape, including changes in the expression of key receptors and co-factors exploited by viruses during the initial steps of infection. These results provide critical biological context for interpreting our single-virus force measurements and demonstrate that tissue maturation directly influences viral attachment properties.
Together, these achievements lay the technological and biological foundations required to address the central goals of the project. The validated nanobiophysical platform, combined with physiologically relevant 3D epithelial systems, now enables us to investigate how viruses engage with their receptors in environments that closely mimic human tissues.

Fortschritte, die über den aktuellen Stand der Technik hinausgehen und voraussichtliche potenzielle Auswirkungen (einschließlich der bis dato erzielten sozioökonomischen Auswirkungen und weiter gefassten gesellschaftlichen Auswirkungen des Projekts)

The project advances the field on multiple fronts. From a technological standpoint, the integrated AFM–optical tweezers system represents a major leap beyond existing methods for studying virus–host interactions. Current approaches typically capture either molecular forces or dynamic information, but not both simultaneously, and rarely within realistic 3D environments. Our platform overcomes these limitations by enabling direct, real-time, single-virus measurements in living tissues that faithfully reproduce the architecture and heterogeneity found in vivo.
Biologically, the project uncovers new relationships between tissue differentiation, receptor expression, and viral binding mechanics. The demonstration that epithelial maturation reshapes viral entry pathways challenges the long-standing assumptions derived from 2D cell models and provides an entirely new framework for understanding infection at the tissue scale. These insights bridge the gap between molecular virology and tissue biology and open the door to a deeper understanding of viral tropism and host susceptibility.
Medically, the results pave the way for identifying new antiviral strategies targeting the earliest steps of infection. By revealing the mechanical and molecular determinants of virus attachment, the project highlights new vulnerability points that can be exploited to block infection before viral entry occurs. The platform further offers unique opportunities for screening drug candidates that modulate virus–receptor interactions or alter the biophysical landscape of epithelial tissues, thereby complementing classical antiviral approaches.
Overall, the project sets the stage for a transformative shift in how viral entry is studied, moving from simplified 2D systems toward fully integrated, physiologically relevant, nanobiophysical analyses. This work will significantly advance our fundamental understanding of viral infection and contribute to the development of innovative antiviral strategies with broad-spectrum potential.