IgG Fc domains that bind C1q but not effector Fcγ receptors delineate the importance of complement-mediated effector functions

  • Nature Immunology volume 18, pages 889898 (2017)
  • doi:10.1038/ni.3770
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Engineered crystallizable fragment (Fc) regions of antibody domains, which assume a unique and unprecedented asymmetric structure within the homodimeric Fc polypeptide, enable completely selective binding to the complement component C1q and activation of complement via the classical pathway without any concomitant engagement of the Fcγ receptor (FcγR). We used the engineered Fc domains to demonstrate in vitro and in mouse models that for therapeutic antibodies, complement-dependent cell-mediated cytotoxicity (CDCC) and complement-dependent cell-mediated phagocytosis (CDCP) by immunological effector molecules mediated the clearance of target cells with kinetics and efficacy comparable to those of the FcγR-dependent effector functions that are much better studied, while they circumvented certain adverse reactions associated with FcγR engagement. Collectively, our data highlight the importance of CDCC and CDCP in monoclonal-antibody function and provide an experimental approach for delineating the effect of complement-dependent effector-cell engagement in various therapeutic settings.

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Change history

  • Corrected online 27 June 2017

    In the version of this article initially published online, the labels identifying each plot in Figure 1b were missing. The labels are as follows (left to right): CHO, FcγRI, FcγRIIaR131, FcγRIIaH131, FcγRIIb, FcγRIIIaF158 and FcγRIIIaV158. Also, the reference cited in the accompanying legend (ref. 21) is incorrect. The correct reference is ref. 14. The errors have been corrected in the print, PDF and HTML versions of this article.


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We thank Y. Tanno for assistance with protein expression; A. Bui for assistance with liquid chromatography–tandem mass spectrometry; P. Tucker (University of Texas at Austin) for cancer cell lines; D. Lee (MD Anderson Cancer Center) for patient-derived primary acute lymphocytic leukemia cells; the Macromolecular Crystallography Facility of the University of Texas at Austin; the Berkeley Center for Structural Biology; the Advanced Light Source (supported by the Director, Office of Science, Office of Basic Energy Sciences, of the US Department of Energy under contract DE-AC02-05CH11231); the Proteomics Facility at the University of Texas at Austin (supported by grant RP110782 from the Cancer Prevention Research Training Program); and A. Nicola and the Plate-Forme d'Imagerie Dynamique (Institut Pasteur, Paris) for help with the bioluminescence experiments. Supported by the Clayton Foundation, the Institut Pasteur (P.B. laboratory), the Institut National de la Santé et de la Recherche Médicale (P.B. laboratory), the European Research CouncilSeventh Frame-work Program (ERC-2013-CoG 616050 for the P.B. laboratory), the Pasteur–Paris University International PhD program (B.B.), the Cancer Prevention Research Training Program (RP140108 to M.D.; RP160015 to H.T.; and RP130570 to N.V.), the American Cancer Society (123506-PF-13-354-01-CDD to N.M.), Uehara Memorial Foundation (H.T.), Japan Society for the Promotion of Science (H.T.), Deutsche Forschungsgemeinschaft (CRC1181-A07 to F.N.), the US National Institutes of Health (R01CA174385 to N.V.; and R01 GM104896 to Y.J.Z.) and the Welch Foundation (F-1778 to Y.J.Z.). The content is solely the responsibility of the authors and does not necessarily represent the official views of the Cancer Prevention and Research Institute of Texas.

Author information

Author notes

    • Moses Donkor
    •  & Nicholas Marshall

    Present addresses: Department of Infection Diseases, MedImmune, Gaithersburg, Maryland, USA (M.D.), and Department of Biochemical Engineering and Structure, Merck, New Jersey, USA (N.M.).


  1. Department of Chemical Engineering, University of Texas at Austin, Austin, Texas, USA.

    • Chang-Han Lee
    • , Makiko Watanabe
    • , Wissam Charab
    • , Jiwon Lee
    • , Moses Donkor
    • , Oana I Lungu
    • , Nicholas Marshall
    • , Tae Hyun Kang
    • , Hidetaka Tanno
    • , George Delidakis
    •  & George Georgiou
  2. Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA.

    • Gabrielle Romain
    •  & Navin Varadarajan
  3. Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas, USA.

    • Wupeng Yan
    • , Kendra Triplett
    • , Yan Jessie Zhang
    •  & George Georgiou
  4. Institut Pasteur, Department of Immunology, Unit of Antibodies in Therapy and Pathology, Paris, France.

    • Biliana Todorova
    • , Odile Richard-Le Goff
    • , Bianca Balbino
    •  & Pierre Bruhns
  5. INSERM, U760, Paris, France.

    • Biliana Todorova
    • , Odile Richard-Le Goff
    • , Bianca Balbino
    •  & Pierre Bruhns
  6. Institute of Genetics, Department of Biology, University of Erlangen-Nürnberg, Erlangen, Germany.

    • Anja Lux
    •  & Falk Nimmerjahn
  7. Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, Virginia, USA.

    • Margaret A Lindorfer
    •  & Ronald P Taylor
  8. Université Pierre et Marie Curie, Paris, France.

    • Bianca Balbino
  9. Department of Biomedical Engineering, University of Texas at Austin, Austin, Texas, USA.

    • Corrine Alford
    •  & George Georgiou
  10. Institute for Cell and Molecular Biology, University of Texas at Austin, Austin, Texas, USA.

    • Yan Jessie Zhang
    •  & George Georgiou
  11. Center for Systems and Synthetic Biology University of Texas at Austin, Austin, Texas, USA.

    • George Georgiou


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C.-H.L. and G.G. conceived of and designed the research; C.-H.L., G.R., W.Y., M.W., W.C., B.T., J.L., K.T., M.D., A.L., N.M., M.A.L., O.R.-L.G., B.B., T.H.K., H.T., G.D. and C.A. performed experiments; C.-H.L, G.R., W.Y., O.I.L., R.P.T., F.N., N.V., P.B., Y.J.Z. and G.G. analyzed data; and C.-H.L, G.R., N.V., P.B., Y.J.Z., and G.G. wrote the paper.

Competing interests

G.G. and C.-H.L. are authors of the approved patent PCT/US2016/017100 9 ('Engineered immunoglobulin Fc polypeptides displaying improved complement activation').

Corresponding author

Correspondence to George Georgiou.

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    Supplementary Figures 1–7 and Supplementary Tables 1–3