Project Details
Projekt
Isolating human neutralizing antibodies targeting adenovirus receptor binding domains
Applicant
Professor Dr. Thomas Krey
Subject Area
Virology
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 548065690
Adenoviruses (AdVs) play a dual role in human health acting both as important human pathogens and as tools for medical intervention (e.g., vaccination or gene therapy). A wealth of structural information is available for the adenoviral receptor binding proteins (i.e., the fiber knob domain and the penton base) alone and in complex with cellular receptor molecules. In contrast, not much is known about human antibodies targeting the adenovirus capsid and to date there are no structural data on how adenovirus capsids are recognized by human neutralizing antibodies. It remains elusive to date, whether broadly neutralizing antibodies could serve as clinically relevant therapeutic approach to treat severe adenovirus infections. The three major targets of neutralizing antibodies are the hexon protein, the penton base and the fiber knob domain. Antibodies targeting the penton base and the fiber knob domain likely utilize a neutralization mechanism based on direct competition, whereas neutralization by hexon-targeting nAbs apparently involves a more complex mechanism. In this project proposal, we will therefore focus on the isolation and characterization of human monoclonal antibodies targeting the penton base and the fiber knob domain. We will initially produce recombinant fiber knob domains of AdVs relevant for vaccine design or gene therapy (HAdV-C5, HAdV-D26 and ChAdOx-1) fused to a fluorophore and use these to isolate antigen-specific memory B cells from peripheral blood mononuclear cells of healthy individuals. Single cell B cell receptor (BCR) sequencing will allow the analysis of the antigen-specific BCR repertoire and facilitate the recombinant production of fiber knob-specific human antibodies for further characterization. We will combine immunological, biochemical and structural approaches to characterize the most interesting human antibodies with respect to neutralization potency, kinetic binding parameters and targeted epitope. In a second step, we will produce recombinant receptor-binding domains (fiber knob domains and penton base) of clinically relevant HAdVs including HAdV-A31, HAdV-C2, HAdV-B55 und HAdV-F41. We will use these proteins to perform a serum screening within a second cohort of healthy individuals and identify antigen-specific memory B cells from healthy individuals with high serum titers using multicolor FACS as described above. Upon single cell sequencing recombinant antibodies will be expressed and selected ones will be characterized immunologically, biochemically and structurally. A comparative analysis of the two obtained BCR repertoires and the characterization of individual antibodies will provide 1) important insights into the interplay between human antibodies and the adenoviral capsid, 2) novel molecules with therapeutic potential and 3) important tools for adenoviral research.
DFG Programme
Research Units
