Development of a highly effective vaccine or antibodies for the prevention and ultimately elimination of malaria is urgently needed. Here we report the isolation of a number of human monoclonal antibodies directed against the Plasmodium falciparum (Pf) circumsporozoite protein (PfCSP) from several subjects immunized with an attenuated Pf whole-sporozoite (SPZ) vaccine (Sanaria PfSPZ Vaccine). Passive transfer of one of these antibodies, monoclonal antibody CIS43, conferred high-level, sterile protection in two different mouse models of malaria infection. The affinity and stoichiometry of CIS43 binding to PfCSP indicate that there are two sequential multivalent binding events encompassing the repeat domain. The first binding event is to a unique 'junctional' epitope positioned between the N terminus and the central repeat domain of PfCSP. Moreover, CIS43 prevented proteolytic cleavage of PfCSP on PfSPZ. Analysis of crystal structures of the CIS43 antigen-binding fragment in complex with the junctional epitope determined the molecular interactions of binding, revealed the epitope's conformational flexibility and defined Asn-Pro-Asn (NPN) as the structural repeat motif. The demonstration that CIS43 is highly effective for passive prevention of malaria has potential application for use in travelers, military personnel and elimination campaigns and identifies a new and conserved site of vulnerability on PfCSP for next-generation rational vaccine design.

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We thank the study volunteers from the malaria clinical trials VRC312 and VRC314. We thank R. Bailer (Vaccine Research Center, National Institutes of Allergy and Infectious Diseases, National Institutes of Health), for providing peripheral blood mononuclear cell samples. We thank R. Lynch, S. Narpala, M. Prabhakaran, R. Nguyen and X. Chen (Vaccine Research Center, National Institutes of Allergy and Infectious Diseases, National Institutes of Health) for technical help and advice regarding the experiments. We thank I. Cockburn (Australian National University College of Health and Medicine) for providing some of the biotinylated (NANP)9 probe used here. We thank T. Zhou (Vaccine Research Center, National Institutes of Allergy and Infectious Diseases, National Institutes of Health) for providing monoclonal antibody VRC01. We thank C. Peckels, A. Foulger, A. Holland and M. Wang (Duke Human Vaccine Institute (DHVI)) for technical assistance and H. Bouton-Verville (DHVI) for project management. We are grateful to C. A. Schramm's expertise and assistance in analyzing the malaria Pf3K database. We thank the Sanaria Manufacturing Team for the production of fresh PfSPZ. We thank M. Nason for technical help with statistical analysis. We thank B. Graham (Vaccine Research Center, National Institutes of Allergy and Infectious Diseases, National Institutes of Health) for insightful discussion regarding the project. We are particularly grateful to L. Stamatatos for use of laboratory space and equipment. We thank the J. B. Pendleton Charitable Trust for its generous support of Formulatrix robotic instruments. This work was supported by the National Institutes of Health grant GM56550 and the National Science Foundation grant MCB-1157506 to E.F. M.P. and C.W. were supported by a Vaccine and Infectious Disease Division Faculty Initiative Grant through the Fred Hutchinson Cancer Research Center. X-ray diffraction data was collected at the Berkeley Center for Structural Biology beamlines 5.0.1 and 5.0.2, which are supported in part by the National Institute of General Medical Sciences, National Institutes of Health. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the United States Department of Energy under contract number DE-AC02-05CH11231. Work done at Duke Universiy has been funded in part with Federal funds from the National Cancer Institute, National Institutes of Health, under Contract No. HHSN261200800001E. Production and characterization of the PfSPZ Vaccine were supported in part by the National Institute of Allergy and Infectious Diseases Small Business Innovation Research Grants 5R44AI058375-08 (to S.L.H.).

The findings and conclusions in this report are those of the authors and do not necessarily reflect the views of the funding agency or collaborators. The views expressed in this publication are those of the authors and do not necessarily reflect the official policy or position of the Department of Health and Human Services or the United States Government.

Author information

Author notes

    • Hua-Xin Liao
    •  & Adam K Wheatley

    Present addresses: College of Life Science and Technology, Jinan University, Guangzhou, China (H.-X.L.) and Department of Microbiology and Immunology, University of Melbourne, Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria, Australia (A.K.W.).

    • Neville K Kisalu
    •  & Azza H Idris

    These authors contributed equally to this work.

    • Marie Pancera
    •  & Robert A Seder

    These authors jointly directed this work.


  1. Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA.

    • Neville K Kisalu
    • , Azza H Idris
    • , Barbara J Flynn
    • , Joseph R Francica
    • , Masaru Kanekiyo
    • , Adam K Wheatley
    • , Adrian B McDermott
    • , S Katie Farney
    • , Gwo-Yu Chuang
    • , Baoshan Zhang
    • , Peter D Kwong
    •  & Robert A Seder
  2. Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.

    • Connor Weidle
    •  & Marie Pancera
  3. Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA.

    • Yevel Flores-Garcia
    • , Jason Gregory
    • , Photini Sinnis
    •  & Fidel Zavala
  4. Seattle Biomedical Research Institute, Seattle, Washington, USA.

    • Brandon K Sack
    • , Sean Murphy
    •  & Stefan H I Kappe
  5. Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA.

    • Arne Schön
    •  & Ernesto Freire
  6. Division of Health Sciences and Technology, Institute for Medical Engineering and Science, and The Broad Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.

    • Alex B Miller
    • , Sandra March
    •  & Sangeeta N Bhatia
  7. Duke Human Vaccine Institute, Durham, North Carolina, USA.

    • Hua-Xin Liao
    • , Barton F Haynes
    • , Kevin Wiehe
    • , Ashley M Trama
    • , Kevin O Saunders
    • , Morgan A Gladden
    • , Anthony Monroe
    •  & Mattia Bonsignori
  8. Department of Medicine, Duke University Medical Center, Durham, North Carolina, USA.

    • Barton F Haynes
    • , Kevin Wiehe
    •  & Mattia Bonsignori
  9. Department of Immunology, Duke University Medical Center, Durham, North Carolina, USA.

    • Barton F Haynes
  10. Department of Surgery, Duke University School of Medicine, Duke University Medical Center, Durham, North Carolina, USA.

    • Kevin O Saunders
  11. Sanaria Inc., Rockville, Maryland, USA.

    • Natasha Kc
    • , Sumana Chakravarty
    • , B Kim Lee Sim
    •  & Stephen L Hoffman


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N.K.K., A.H.I., B.K.S., M.P., F.Z. and R.A.S. planned the studies. N.K.K., A.H.I., B.K.S., S. Murphy, C.W., Y.F.-G., B.J.F., A.S., J.R.F., S. March, A.B.M., M.K., A.K.W., S.K.F., G.-Y.C., S.C., N.K., B.Z., J.G., P.S. and M.P. conducted experiments. F.Z. provided mouse monoclonal antibodies 2A10 and 5D5. K.W., K.O.S., A.M.T., M.A.G. and A.M. contributed new methodologies, analytic tools and performed research. M.B., H.-X.L. and B.F.H. isolated, cloned and produced plasmablast antibodies and analyzed data. N.K.K., A.H.I., B.K.S., F.Z., S.H.I.K., S.C., A.S., E.F., S. March, A.B.M., P.D.K., P.S., S.N.B., B.K.L.S., S.L.H., M.P. and R.A.S. interpreted results from the studies. N.K.K., A.H.I., M.P. and R.A.S. wrote the paper. All authors reviewed, edited and approved the paper.

Competing interests

N.K., S.C., B.K.L.S. and S.L.H. are salaried employees of Sanaria Inc., the developer and owner of the PfSPZ Vaccine and the sponsor of the clinical trials. In addition, S.L.H. and B.K.L.S. have a financial interest in Sanaria Inc. All other authors declare no competing financial interests.

Corresponding authors

Correspondence to Marie Pancera or Robert A Seder.

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