Cross-reactive antibodies targeting surface-exposed non-structural protein 1 (NS1) of dengue virus-infected cells recognize epitopes on the spaghetti loop of the β-ladder domain
Issued Date
2022-05-01
Resource Type
eISSN
19326203
Scopus ID
2-s2.0-85130855308
Pubmed ID
35617160
Journal Title
PLoS ONE
Volume
17
Issue
5 May
Rights Holder(s)
SCOPUS
Bibliographic Citation
PLoS ONE Vol.17 No.5 May (2022)
Suggested Citation
Kraivong R., Traewachiwiphak S., Nilchan N., Tangthawornchaikul N., Pornmun N., Poraha R., Sriruksa K., Limpitikul W., Avirutnan P., Malasit P., Puttikhunt C. Cross-reactive antibodies targeting surface-exposed non-structural protein 1 (NS1) of dengue virus-infected cells recognize epitopes on the spaghetti loop of the β-ladder domain. PLoS ONE Vol.17 No.5 May (2022). doi:10.1371/journal.pone.0266136 Retrieved from: https://repository.li.mahidol.ac.th/handle/123456789/86515
Title
Cross-reactive antibodies targeting surface-exposed non-structural protein 1 (NS1) of dengue virus-infected cells recognize epitopes on the spaghetti loop of the β-ladder domain
Other Contributor(s)
Abstract
Non-structural protein 1 (NS1) is a glycoprotein component of dengue virus (DENV) that is essential for viral replication, infection and immune evasion. Immunization with NS1 has been shown to elicit antibody-mediated immune responses which protect mice against DENV infections. Here, we obtained peripheral blood mononuclear cells from human subjects with secondary dengue infections, which were used to construct a dengue immune phage library displaying single-chain variable fragments. Phage selective for DENV NS1 were obtained by biopanning. Twenty-one monoclonal antibodies (mAbs) against DENV NS1 were generated from the selected phage and characterized in detail. We found most anti-NS1 mAbs used IGHV1 heavy chain antibody genes. The mAbs were classified into strongly and weakly-reactive groups based on their binding to NS1 expressed in dengue virus 2 (DENV2)-infected cells. Antibody binding experiments with recombinant NS1 proteins revealed that the mAbs recognize conformational epitopes on the β-ladder domain (amino acid residues 178–273) of DENV NS1. Epitope mapping studies on alanine-substituted NS1 proteins identified distinct but overlapping epitopes. Protruding amino acids distributed around the spaghetti loop are required for the binding of the strongly-reactive mAbs, whereas the recognition residues of the weakly-reactive mAbs are likely to be located in inaccessible sites facing toward the cell membrane. This information could guide the design of an NS1 epitope-based vaccine that targets cross-reactive conserved epitopes on cell surface-associated DENV NS1.