Human monoclonal antibody (mAb) therapy offers considerable advantages for prophylaxis, preemptive and acute treatment in viral outbreak settings, yet its'use as a therapeutic agent against emerging viral pathogens has been protracted because of longstanding barriers such as antigenic variability of circulating viral strains and neutralization escape, particularly for RNA respiratory pathogens such as coronaviruses (CoVs) and influenza. Importantly, cost of manufacturing, a historically perceived limitation of mAb-based immunotherapy has dramatically decreased in recent years. Here, the Marasco, Baric and Liddington labs propose to develop platforms for rapidly identifying broad-spectrum neutralizing human mAbs (BnAbs) that are effective against emerging epidemic and zoonotic pool strains, using SARS-CoV as a model. Major strengths of this model include robust sequence database of epidemic and zoonotic isolates, synthetic genomics and reverse genetics and in vivo pathogenesis models in young and aged mice that recapitulate severe human end-stage lung disease and ARDS;atomic structures of SARS-CoV receptor ACE2 and human BnAbs bound to its Spike protein;and well developed methodologies and novel reagents developed by our collaborative team. Our approach is based on our published data that BnAbs can be designed to either prevent virus neutralization escape and/or attenuate virus evolution. Information gained from in vitro studies will be used to develop, in parallel, new strategies for maximizing vaccine efficacy against the broader heterogeneous pool of animal strains. The impact of these studies will be high, providing a template for similar design platforms for other important human emerging pathogens. Specifically, we will further build on our discovery of the potent human anti-SARS mAb 80R that is directed to the receptor binding motif (RBM) on Spike protein, and BnAb derivatives of 80R that have been subsequently engineered to be active against all SARS-CoV isolates from humans and animals (except bats). It is now known that the natural reservoir of many human pathogenic CoVs is the bat, where ancestral CoVs, including the bat-SARS-CoV, can replicate, recombine and reemerge as new human pathogens. The bat reservoir of SARS-CoVs is firmly established, and from the public health standpoint, emerging and re-emerging SARS-CoVs represent a real threat to human health. We propose to simultaneously develop BnAbs against the conserved S2 domain of SARS-CoVs, which may have even greater breadth (including activity against new SARS-like-CoVs and other pathogenic CoVs that might emerge from bats in the future), potency of neutralization and resistance to neutralization escape. In 4 specific aims, we will test 12 hypotheses that relate to defining new nAbs against SARS-CoVs, their neutralizing epitopes, escape mechanisms and strategies to prevent neutralization escape. Co-crystal structures of BnAbs-Spike complexes solved during these studies will guide our virologic studies and antibody engineering efforts. The information gained from in vitro neutralization escape studies will also be used to design prototypic RBM- and S2-directed vaccine studies to determine if we can control the type of nAbs that are elicited, their breadth of neutralization and their resistance to neutralization escape, with the goal of eliciting BnAb responses that can block virus evolution.

Public Health Relevance

Severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is a novel virus that caused the global outbreak of SARS in 2002/03 with 10% mortality and a cluster of cases in 2003/04. Recently, it was discovered that bats harbor the ancestors of SARS-CoV and many if not all human CoV respiratory pathogens. Currently, there are no approved therapies for prevention and treatment of pathogenic CoV infections, which could reemerge at anytime and become a serious threat to human health. This project will develop a human antibody cocktail for this unmet need.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI085524-02
Application #
8080843
Study Section
Vaccines Against Microbial Diseases (VMD)
Program Officer
Salomon, Rachelle
Project Start
2010-06-09
Project End
2015-05-31
Budget Start
2011-06-01
Budget End
2012-05-31
Support Year
2
Fiscal Year
2011
Total Cost
$1,117,743
Indirect Cost
Name
Dana-Farber Cancer Institute
Department
Type
DUNS #
076580745
City
Boston
State
MA
Country
United States
Zip Code
02215
Johnson, Reed F; Bagci, Ulas; Keith, Lauren et al. (2016) 3B11-N, a monoclonal antibody against MERS-CoV, reduces lung pathology in rhesus monkeys following intratracheal inoculation of MERS-CoV Jordan-n3/2012. Virology 490:49-58
Corti, Davide; Zhao, Jincun; Pedotti, Mattia et al. (2015) Prophylactic and postexposure efficacy of a potent human monoclonal antibody against MERS coronavirus. Proc Natl Acad Sci U S A 112:10473-8
Huang, Xingchuan; Dong, Wenjuan; Milewska, Aleksandra et al. (2015) Human Coronavirus HKU1 Spike Protein Uses O-Acetylated Sialic Acid as an Attachment Receptor Determinant and Employs Hemagglutinin-Esterase Protein as a Receptor-Destroying Enzyme. J Virol 89:7202-13
Tang, Xian-Chun; Marasco, Wayne A (2015) Human neutralizing antibodies against MERS coronavirus: implications for future immunotherapy. Immunotherapy 7:591-4
Menachery, Vineet D; Yount Jr, Boyd L; Debbink, Kari et al. (2015) A SARS-like cluster of circulating bat coronaviruses shows potential for human emergence. Nat Med 21:1508-13
Agnihothram, Sudhakar; Gopal, Robin; Yount Jr, Boyd L et al. (2014) Evaluation of serologic and antigenic relationships between middle eastern respiratory syndrome coronavirus and other coronaviruses to develop vaccine platforms for the rapid response to emerging coronaviruses. J Infect Dis 209:995-1006
Sui, Jianhua; Deming, Meagan; Rockx, Barry et al. (2014) Effects of human anti-spike protein receptor binding domain antibodies on severe acute respiratory syndrome coronavirus neutralization escape and fitness. J Virol 88:13769-80
Tang, Xian-Chun; Agnihothram, Sudhakar S; Jiao, Yongjun et al. (2014) Identification of human neutralizing antibodies against MERS-CoV and their role in virus adaptive evolution. Proc Natl Acad Sci U S A 111:E2018-26
Chan, Renee W Y; Chan, Michael C W; Agnihothram, Sudhakar et al. (2013) Tropism of and innate immune responses to the novel human betacoronavirus lineage C virus in human ex vivo respiratory organ cultures. J Virol 87:6604-14
Scobey, Trevor; Yount, Boyd L; Sims, Amy C et al. (2013) Reverse genetics with a full-length infectious cDNA of the Middle East respiratory syndrome coronavirus. Proc Natl Acad Sci U S A 110:16157-62

Showing the most recent 10 out of 13 publications