bioRxiv Science⌕ Search

bioRxiv · 10.1101/2020.03.21.990770

Potent human neutralizing antibodies elicited by SARS-CoV-2 infection

Abstract

The pandemic caused by emerging coronavirus SARS-CoV-2 presents a serious global public health emergency in urgent need of prophylactic and therapeutic interventions. SARS-CoV-2 cellular entry depends on binding between the viral Spike protein receptor-binding domain (RBD) and the angiotensin converting enzyme 2 (ACE2) target cell receptor. Here, we report on the isolation and characterization of 206 RBD-specific monoclonal antibodies (mAbs) derived from single B cells of eight SARS-CoV-2 infected individuals. These mAbs come from diverse families of antibody heavy and light chains without apparent enrichment for particular families in the repertoire. In samples from one patient selected for further analyses, we found coexistence of germline and germline divergent clones. Both clone types demonstrated impressive binding and neutralizing activity against pseudovirus and live SARS-CoV-2. However, the antibody neutralizing potency is determined by competition with ACE2 receptor for RBD binding. Surprisingly, none of the SARS-CoV-2 antibodies nor the infected plasma cross-reacted with RBDs from either SARS-CoV or MERS-CoV although substantial plasma cross-reactivity to the trimeric Spike proteins from SARS-CoV and MERS-CoV was found. These results suggest that antibody response to RBDs is viral species-specific while that cross-recognition target regions outside the RBD. The specificity and neutralizing characteristics of this plasma cross-reactivity requires further investigation. Nevertheless, the diverse and potent neutralizing antibodies identified here are promising candidates for prophylactic and therapeutic SARS-CoV-2 interventions.

Source connections

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Ju, B., Zhang, Q., Ge, X., Wang, R., Yu, J., Shan, S., Zhou, B., Song, S., Tang, X., Ge, J., Lan, J., Yuan, J., Wang, H., Zhao, J., Zhang, S., Wang, Y., Shi, X., Liu, L., Wang, X., Zhang, Z., Zhang, L.. 2020-03-25. Potent human neutralizing antibodies elicited by SARS-CoV-2 infection. https://doi.org/10.1101/2020.03.21.990770

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

Proteome-wide discovery of novel diagnostic antigens for coccidioidomycosis

Coccidioidomycosis, commonly called Valley Fever (VF), caused by Coccidioides spp., is an understudied fungal disease that accounts for a substantial fraction of pneumonias in endemic areas. Diagnosis remains challenging because the mainstay of diagnosis is serology, and current assays have modest sensitivity in early infection. Discovery of new antigens could improve serologic detection early in disease. Here, we use PepSeq, a DNA-programmable serology platform, to represent the complete proteome of Coccidioides within a library of 244,000 DNA-barcoded peptides. By profiling antibody reactivity at the protein and epitope levels in VF patients, naturally infected pigtail macaques, and healthy controls, we identify numerous previously-unrecognized antigens and epitopes, including some shared between humans and macaque responses. When translated into a pooled peptide ELISA, we show that a subset of identified antigens can discriminate VF cases from controls in an independent cohort with high accuracy (AUC = 0.91). These findings establish high-dimensional peptide serology as a scalable approach for fungal antigen discovery and identify new targets for improved VF diagnosis.

immunology↗

Establishing an ex vivo platform for molecular profiling of skin structural cells using frozen human skin biopsies

Skin structural cells, including keratinocytes, melanocytes, endothelial cells, and fibroblasts, play critical roles in the development of chronic inflammatory skin disease. Inflammatory stimuli induce transcriptional reprogramming and epigenetic changes in skin structural cells, which contribute to disease pathogenesis. Although two-dimensional (2D) and three-dimensional (3D) skin culture models have been widely used to investigate inflammatory responses in skin structural cells, ex vivo systems that maintain skin structure and cellular composition remain limited. To address this gap, we explored using frozen skin biopsies as an experimental platform to study the responses of skin structural cells to inflammatory stimuli. Using a simple air-liquid interface culture method on permeable Transwell inserts, we showed that viable skin structural cells that retain cell-type-specific transcriptional profiles can be recovered from frozen skin biopsies after prolonged in vitro culture. Stimulation with IFN-{gamma} induced robust transcriptional and chromatin accessibility changes that were largely resolved after stimulus removal, with transcriptional responses to secondary stimulation comparable to the primary stimulation. Treatment of cultured skin biopsies with histone-modifying enzyme inhibitors effectively altered global histone modification levels, but did not substantially affect the transcriptional resolution of IFN-{gamma}-induced responses. Collectively, these findings establish cryopreserved human skin biopsies as a scalable ex vivo platform that enables mechanistic studies of inflammatory responses of multiple populations of skin structural cells.

immunology↗

γδ T cell-derived IL-17A aggravates experimental epidermolysis bullosa acquisita in response to IL-1β

Epidermolysis bullosa acquisita (EBA) is a mucocutaneous autoimmune blistering disorder mediated by autoantibodies against type VII collagen and subsequent splitting of the dermal-epidermal junction. Interleukin (IL)-17A promotes the production of chemokines and cytokines involved in neutrophil recruitment and activation, suggesting that IL-17A may contribute to EBA pathogenesis. We aimed to clarify the role of IL-17A in experimental EBA. Using an antibody transfer-induced EBA mouse model, we demonstrate that IL-17A promotes disease development, as pharmacological blockade of IL-17A with a neutralizing antibody ameliorated skin lesions. Gamma-delta ({gamma}{delta}) T cells were identified as the predominant cellular source of IL-17A, supported by the attenuated disease phenotype observed in {gamma}{delta}TCR-deficient mice. In addition, CD4+ T cells and neutrophils contributed to IL-17A production in experimental EBA. Mechanistically, IL-1-beta, rather than IL-23, was identified as a critical mediator of IL-17A production by {gamma}{delta} T cells in vitro, consistent with our in vivo findings. Whereas EBA severity was not reduced in IL-23p19-deficient mice, disease was markedly attenuated in IL-1R-deficient animals. Together, our study provides the first evidence that {gamma}{delta} T cell-derived IL-17A plays a pivotal role in experimental EBA and identifies a previously unrecognized IL-1{beta}/{gamma}{delta} T cell/IL-17A axis that expands current understanding of EBA immunopathogenesis.

immunology↗