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bioRxiv · 10.1101/661918

Development of a potent and protective germline-like antibody lineage against Zika virus in a convalescent human

Abstract

Zika virus (ZIKV) specific neutralizing antibodies hold a great promise for antibody-based interventions and vaccine design against ZIKV infection. However, their development in infected patients remain unknown. Here, we report on the dynamic development of a potent and protective ZIKV-specific human antibody ZK2B10 initially isolated from a ZIKV convalescent individual using next-generation sequencing (NGS). The unbiased repertoire analysis showed dramatic changes in many families of heavy and light chain variable regions. However, lineage tracing of ZK2B10 revealed limited somatic hypermutation throughout the 12 months since the onset of symptom. In particular, NGS-derived germline-like somatic variants neutralized and protected mice from lethal challenge of ZIKV without detectable cross-reactivity with Dengue virus (DENV). Site-directed mutagenesis identified two residues within {lambda} chain, N31 and S91 that are essential to the functional maturation. The dynamic features unveiled here will assist us to better understand the pathogenesis of ZIKV infection and inform rational design of vaccines.\n\nAuthor summaryRecently emerged ZIKV is associated with severe neurological complications such as Guillain-Barre syndrome in adults and congenital microcephaly in newborns. No ZIKV-specific therapeutics or vaccines are currently available. We and others have identified a number of neutralizing antibodies capable of protecting experimental animals from ZIKV infection. However, the development of these potent antibodies during ZIKV natural infection remains unknown. Here, we report on the longitudinal analysis of one such antibody ZK2B10 using next-generation sequencing (NGS), bioinformatics and functional analysis. We found that the ZK2B10 germline-like antibodies possess strong neutralizing activity in vitro and impressive protectivity against lethal ZIKV infection in vivo. These findings suggest that the potent and protective antibody response against ZIKV can be generated within relative short term with high germline identity which provide great hope and promise for successful vaccine development against ZIKV.

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BibTeXRIS

Gao, F., Lin, X., He, L., Wang, R., Wang, H., Shi, X., Zhang, F., Yin, C., Zhang, L., Zhu, J., Yu, L.. 2019-06-05. Development of a potent and protective germline-like antibody lineage against Zika virus in a convalescent human. https://doi.org/10.1101/661918

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