7K76

Crystal structure of MAD2-6 IgG Fab in complex with PfCSP N-terminal peptide.


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.14 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.185 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Functional human IgA targets a conserved site on malaria sporozoites.

Tan, J.Cho, H.Pholcharee, T.Pereira, L.S.Doumbo, S.Doumtabe, D.Flynn, B.J.Schon, A.Kanatani, S.Aylor, S.O.Oyen, D.Vistein, R.Wang, L.Dillon, M.Skinner, J.Peterson, M.Li, S.Idris, A.H.Molina-Cruz, A.Zhao, M.Olano, L.R.Lee, P.J.Roth, A.Sinnis, P.Barillas-Mury, C.Kayentao, K.Ongoiba, A.Francica, J.R.Traore, B.Wilson, I.A.Seder, R.A.Crompton, P.D.

(2021) Sci Transl Med 13

  • DOI: 10.1126/scitranslmed.abg2344
  • Primary Citation of Related Structures:  
    7K76

  • PubMed Abstract: 
  • Immunoglobulin (Ig)A antibodies play a critical role in protection against mucosal pathogens. However, the role of serum IgA in immunity to nonmucosal pathogens, such as Plasmodium falciparum , is poorly characterized, despite being the second most abundant isotype in blood after IgG ...

    Immunoglobulin (Ig)A antibodies play a critical role in protection against mucosal pathogens. However, the role of serum IgA in immunity to nonmucosal pathogens, such as Plasmodium falciparum , is poorly characterized, despite being the second most abundant isotype in blood after IgG. Here, we investigated the circulating IgA response in humans to P. falciparum sporozoites that are injected into the skin by mosquitoes and migrate to the liver via the bloodstream to initiate malaria infection. We found that circulating IgA was induced in three independent sporozoite-exposed cohorts: individuals living in an endemic region in Mali, malaria-naïve individuals immunized intravenously with three large doses of irradiated sporozoites, and malaria-naïve individuals exposed to a single controlled mosquito bite infection. Mechanistically, we found evidence in an animal model that IgA responses were induced by sporozoites at dermal inoculation sites. From malaria-resistant individuals, we isolated several IgA monoclonal antibodies that reduced liver parasite burden in mice. One antibody, MAD2-6, bound to a conserved epitope in the amino terminus of the P. falciparum circumsporozoite protein, the dominant protein on the sporozoite surface. Crystal structures of this antibody revealed a unique mode of binding whereby two Fabs simultaneously bound either side of the target peptide. This study reveals a role for circulating IgA in malaria and identifies the amino terminus of the circumsporozoite protein as a target of functional antibodies.


    Organizational Affiliation

    Malaria Infection Biology and Immunity Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA. tanj4@nih.gov pcrompton@niaid.nih.gov.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Heavy chain of MAD2-6 IgG FabA, C [auth H]226Homo sapiensMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Light chain of MAD2-6 IgG FabB, D [auth L]213Homo sapiensMutation(s): 0 
Protein Feature View
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  • Reference Sequence
  • Find similar proteins by:  Sequence   |   Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
PfCSP N-terminal peptide P17E [auth P]15Plasmodium falciparumMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.14 Å
  • R-Value Free: 0.218 
  • R-Value Work: 0.184 
  • R-Value Observed: 0.185 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 69.39α = 90
b = 77.32β = 90
c = 181.15γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
MOSFLMdata reduction
Aimlessdata scaling
PHASERphasing

Structure Validation

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Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Bill & Melinda Gates FoundationUnited StatesOPP1170236

Revision History  (Full details and data files)

  • Version 1.0: 2021-06-23
    Type: Initial release
  • Version 1.1: 2021-07-28
    Changes: Database references