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Updated: May 15, 2026

Profiling of Surface Protein Epitopes on Viral Particles by Multiplex Dual-Reporter Strategy
Published on: January 12, 2024
Collectin-11, a complement pattern recognition molecule, mediates pulmonary SARS-CoV-2 neutralization and protection
Adrian Sutta1, Anna Offersgaard2,3, Carlos Rene Duarte Hernandez2,3
1Laboratory of Molecular Medicine, Department of Clinical Immunology, Copenhagen University Hospital, Copenhagen, Denmark.
Background:
Collectin-11 (CL-11) is a complement-activating pattern recognition molecule with structural and functional similarities to mannose-binding lectin (MBL), produced in different tissues, including lung epithelium. Given its tissue localization and role in innate immunity, we investigated its potential to recognize and neutralize severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and to activate complement.
Methods:
We produced recombinant CL-11, MBL, as well as wild-type, variant, and glycan-mutated SARS-CoV-2 Spike (S) proteins. We evaluated CL-11 binding to the S protein, complement activation, and inhibition of S protein-receptor binding using ELISA, as well as neutralization of SARS-CoV-2 in cell-based neutralization assays.
Results:
CL-11 bound different SARS-CoV-2 S protein variants with similar binding preferences as MBL, targeting multiple glycan sites. Upon S protein binding, CL-11 mediated activation of both the lectin and alternative complement pathways, and inhibited S protein-receptor binding. Notably, CL-11 neutralized SARS-CoV-2, inhibiting infection of permissive cells.
Conclusion:
CL-11 binds different SARS-CoV-2 variants and neutralizes SARS-CoV-2 in an antibody-independent manner, suggesting a crucial role in early-stage infection control.
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