Antiviral Activity of a Llama-Derived Single-Domain Antibody against Enterovirus A71
- 21 April 2020
- journal article
- research article
- Published by American Society for Microbiology in Antimicrobial Agents and Chemotherapy
- Vol. 64 (5)
- https://doi.org/10.1128/aac.01922-19
Abstract
In the past few decades, enterovirus A71 (EVA71) has caused devastating outbreaks in the Asia-Pacific region, resulting in serious sequelae in infected young children. No preventive or therapeutic interventions are currently available for curing EVA71 infection, highlighting a great unmet medical need for this disease. Here, we showed that one novel single-domain antibody (sdAb), F1, isolated from an immunized llama, could alleviate EVA71 infection both in vitro and in vivo. We also confirmed that the sdAb clone F1 recognizes EVA71 through a novel conformational epitope comprising the highly conserved region of VP3 capsid protein by using competitive-binding and overlapping-peptide enzyme-linked immunosorbent assays (ELISAs). Because of the virion’s icosahedral structure, we reasoned that adjacent epitopes must be clustered within molecular ranges that may be simultaneously bound by an engineered antibody with multiple valency. Therefore, two single-domain binding modules (F1) were fused to generate an sdAb-in-tandem design so that the capture of viral antigens could be further increased by valency effects. We showed that the tetravalent construct F1×F1-hFc, containing two sdAb-in-tandem on a fragment crystallizable (Fc) scaffold, exhibits more potent neutralization activity against EVA71 than does the bivalent sdAb F1-hFc by at least 5.8-fold. We also demonstrated that, using a human scavenger receptor class B member 2 (hSCARB2) transgenic mouse model, a half dose of the F1×F1-hFc provided better protection against EVA71 infection than did the F1-hFc. Thus, our study furnishes important insights into multivalent sdAb engineering against viral infection and provides a novel strategic deployment approach for preparedness of emerging infectious diseases such as EVA71.Funding Information
- Ministry of Science and Technology, Taiwan (MOST 107-3017-F-182-001)
- Chang Gung Memorial Hospital, Linkou (CMRPD1E0401-403)
- Ministry of Economic Affairs (104-EC-17-A-22-1310)
This publication has 54 references indexed in Scilit:
- An alpaca nanobody inhibits hepatitis C virus entry and cell-to-cell transmissionHepatology, 2013
- Identification of BPR3P0128 as an Inhibitor of Cap-Snatching Activities of Influenza VirusAntimicrobial Agents and Chemotherapy, 2012
- Enterovirus 71 viral capsid protein linear epitopes: Identification and characterizationVirology Journal, 2012
- Characterization of an Isotype-Dependent Monoclonal Antibody against Linear Neutralizing Epitope Effective for Prophylaxis of Enterovirus 71 InfectionPLOS ONE, 2012
- Heavy chain-only antibodies and tetravalent bispecific antibody neutralizing Staphylococcus aureus leukotoxinsProceedings of the National Academy of Sciences of the United States of America, 2011
- Identification and characterization of a cross-neutralization epitope of Enterovirus 71Vaccine, 2011
- Purification and Characterization of Enterovirus 71 Viral Particles Produced from Vero Cells Grown in a Serum-Free Microcarrier Bioreactor SystemPLOS ONE, 2011
- Nanobodies With In Vitro Neutralizing Activity Protect Mice Against H5N1 Influenza Virus InfectionThe Journal of Infectious Diseases, 2011
- Neutralization Efficiency Is Greatly Enhanced by Bivalent Binding of an Antibody to Epitopes in the V4 Region and the Membrane-Proximal External Region within One Trimer of Human Immunodeficiency Virus Type 1 GlycoproteinsJournal of Virology, 2010
- An Epidemic of Enterovirus 71 Infection in TaiwanThe New England Journal of Medicine, 1999