No immunogen to date has reliably elicited broadly neutralizing antibodies to HIV in humans or animal models. Advances in the design of immunogens that antigenically mimic the HIV envelope glycoprotein (Env), such as the soluble cleaved trimer BG505 SOSIP1, have improved the elicitation of potent isolate-specific antibody responses in rabbits2 and macaques3, but so far failed to induce broadly neutralizing antibodies. One possible reason for this failure is that the relevant antibody repertoires are poorly suited to target the conserved epitope regions on Env, which are somewhat occluded relative to the exposed variable epitopes. Here, to test this hypothesis, we immunized four cows with BG505 SOSIP. The antibody repertoire of cows contains long third heavy chain complementary determining regions (HCDR3) with an ultralong subset that can reach more than 70 amino acids in length4,5,6,7,8,9. Remarkably, BG505 SOSIP immunization resulted in rapid elicitation of broad and potent serum antibody responses in all four cows. Longitudinal serum analysis for one cow showed the development of neutralization breadth (20%, n = 117 cross-clade isolates) in 42 days and 96% breadth (n = 117) at 381 days. A monoclonal antibody isolated from this cow harboured an ultralong HCDR3 of 60 amino acids and neutralized 72% of cross-clade isolates (n = 117) with a potent median IC50 of 0.028 μg ml−1. Breadth was elicited with a single trimer immunogen and did not require additional envelope diversity. Immunization of cows may provide an avenue to rapidly generate antibody prophylactics and therapeutics to address disease agents that have evolved to avoid human antibody responses.

Access optionsAccess options

Rent or Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.


Primary accessions

NCBI Reference Sequence


  1. 1.

    et al. A next-generation cleaved, soluble HIV-1 Env trimer, BG505 SOSIP.664 gp140, expresses multiple epitopes for broadly neutralizing but not non-neutralizing antibodies. PLoS Pathog. 9, e1003618 (2013)

  2. 2.

    et al. Holes in the glycan shield of the native HIV envelope are a target of trimer-elicited neutralizing antibodies. Cell Reports 16, 2327–2338 (2016)

  3. 3.

    . et al. HIV-1 neutralizing antibodies induced by native-like envelope trimers. Science 349, aac4223 (2015)

  4. 4.

    , & Use of a single VH family and long CDR3s in the variable region of cattle Ig heavy chains. Int. Immunol. 9, 189–199 (1997)

  5. 5.

    , & A single VH family and long CDR3s are the targets for hypermutation in bovine immunoglobulin heavy chains. Immunol. Rev. 162, 55–66 (1998)

  6. 6.

    , , & Exceptionally long CDR3H region with multiple cysteine residues in functional bovine IgM antibodies. Eur. J. Immunol. 29, 2420–2426 (1999)

  7. 7.

    & Extensive CDR3H length heterogeneity exists in bovine foetal VDJ rearrangements. Scand. J. Immunol. 55, 140–148 (2002)

  8. 8.

    , & Structural and genetic diversity in antibody repertoires from diverse species. Curr. Opin. Struct. Biol. 33, 27–41 (2015)

  9. 9.

    et al. Reshaping antibody diversity. Cell 153, 1379–1393 (2013)

  10. 10.

    et al. Broad neutralization coverage of HIV by multiple highly potent antibodies. Nature 477, 466–470 (2011)

  11. 11.

    et al. Developmental pathway for potent V1V2-directed HIV-neutralizing antibodies. Nature 509, 55–62 (2014)

  12. 12.

    et al. Analysis of a clonal lineage of HIV-1 envelope V2/V3 conformational epitope-specific broadly neutralizing antibodies and their inferred unmutated common ancestors. J. Virol. 85, 9998–10009 (2011)

  13. 13.

    et al. Comparative analysis of human and mouse immunoglobulin variable heavy regions from IMGT/LIGM-DB with IMGT/HighV-QUEST. Theor. Biol. Med. Model. 11, 30 (2014)

  14. 14.

    et al. Complete humanization of the mouse immunoglobulin loci enables efficient therapeutic antibody discovery. Nat. Biotechnol. 32, 356–363 (2014)

  15. 15.

    et al. The functional repertoire of rabbit antibodies and antibody discovery via next-generation sequencing. MAbs 6, 628–636 (2014)

  16. 16.

    , , & Bovine IgM antibodies with exceptionally long complementarity-determining region 3 of the heavy chain share unique structural properties conferring restricted VH + Vlambda pairings. Int. Immunol. 15, 845–853 (2003)

  17. 17.

    et al. Trimeric gp120-specific bovine monoclonal antibodies require cysteine and aromatic residues in CDRH3 for high affinity binding to HIV Env. MAbs 9, 550–566 (2016)

  18. 18.

    et al. Repeated vaccination of cows with HIV Env gp140 during subsequent pregnancies elicits and sustains an enduring strong Env-binding and neutralising antibody response. PLoS ONE 11, e0157353 (2016)

  19. 19.

    et al. Hyperimmune bovine colostrum as a low-cost, large-scale source of antibodies with broad neutralizing activity for HIV-1 envelope with potential use in microbicides. Antimicrob. Agents Chemother. 56, 4310–4319 (2012)

  20. 20.

    et al. Global panel of HIV-1 Env reference strains for standardized assessments of vaccine-elicited neutralizing antibodies. J. Virol. 88, 2489–2507 (2014)

  21. 21.

    et al. Recombinant HIV envelope trimer selects for quaternary-dependent antibodies targeting the trimer apex. Proc. Natl Acad. Sci. USA 111, 17624–17629 (2014)

  22. 22.

    et al. HIV vaccine design to target germline precursors of glycan-dependent broadly neutralizing antibodies. Immunity 45, 483–496 (2016)

  23. 23.

    et al. Structural basis for broad and potent neutralization of HIV-1 by antibody VRC01. Science 329, 811–817 (2010)

  24. 24.

    , , & Topical gel formulation of broadly neutralizing anti-HIV-1 monoclonal antibody VRC01 confers protection against HIV-1 vaginal challenge in a humanized mouse model. Virology 432, 505–510 (2012)

  25. 25.

    et al. Molecular evolution of broadly neutralizing Llama antibodies to the CD4-binding site of HIV-1. PLoS Pathog. 10, e1004552 (2014)

  26. 26.

    et al. Potent and broad neutralization of HIV-1 by a llama antibody elicited by immunization. J. Exp. Med. 209, 1091–1103 (2012)

  27. 27.

    et al. Automated molecular microscopy: the new Leginon system. J. Struct. Biol. 151, 41–60 (2005)

  28. 28.

    , , & & Carragher, B. DoG Picker and TiltPicker: software tools to facilitate particle selection in single particle electron microscopy. J. Struct. Biol. 166, 205–213 (2009)

  29. 29.

    , & Topology representing network enables highly accurate classification of protein images taken by cryo electron-microscope without masking. J. Struct. Biol. 143, 185–200 (2003)

  30. 30.

    et al. Appion: an integrated, database-driven pipeline to facilitate EM image processing. J. Struct. Biol. 166, 95–102 (2009)

  31. 31.

    ., ., . & Accelerated cryo-EM structure determination with parallelisation using GPUs in RELION-2. eLife 5, 19 (2016)

  32. 32.

    et al. UCSF Chimera—a visualization system for exploratory research and analysis. J. Comput. Chem. 25, 1605–1612 (2004)

  33. 33.

    et al. Efficient generation of monoclonal antibodies from single human B cells by single cell RT–PCR and expression vector cloning. J. Immunol. Methods 329, 112–124 (2008)

  34. 34.

    et al. A vaginal fluid simulant. Contraception 59, 91–95 (1999)

  35. 35.

    et al. Minimally mutated HIV-1 broadly neutralizing antibodies to guide reductionist vaccine design. PLoS Pathog. 12, e1005815 (2016)

  36. 36.

    et al. Geneious Basic: an integrated and extendable desktop software platform for the organization and analysis of sequence data. Bioinformatics 28, 1647–1649 (2012)

Download references


This work was supported by the International AIDS Vaccine Initiative Neutralizing Antibody Consortium through the Collaboration for AIDS Vaccine Discovery grant OPP1084519 (D.R.B., I.A.W., A.B.W.), NIH grants R21 AI120791 (V.V.S.), R01 GM105826 (V.V.S.), Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery Grant UM1AI100663 (D.R.B., I.A.W., A.B.W.), IOS 1257829 (M.F.C.), and USDA-NIFA grant number CSREES 2008-35204 (W.M.). D.R.B. acknowledges the support of the James and Jessie Minor Chair in Immunology. We thank B. Schief and S. Menis for providing MD39 for competition experiments. This work was funded in part by IAVI and made possible by the support of many donors, including: the Bill & Melinda Gates Foundation, the Ministry of Foreign Affairs of Denmark, Irish Aid, the Ministry of Finance of Japan in partnership with The World Bank, the Ministry of Foreign Affairs of the Netherlands, the Norwegian Agency for Development Cooperation (NORAD), the United Kingdom Department for International Development (DFID), and the United States Agency for International Development (USAID). The full list of IAVI donors is available at http://www.iavi.org. The contents of this manuscript do not necessarily reflect the views of USAID or the US Government.

Author information

Author notes

    • Devin Sok
    •  & Khoa M. Le

    These authors contributed equally to this work.


  1. Department of Immunology and Microbiology, The Scripps Research Institute, La Jolla, California 92037, USA

    • Devin Sok
    • , Khoa M. Le
    • , Karen L. Saye-Francisco
    • , Joseph G. Jardine
    • , Jennifer Ruiz
    • , Alejandra Ramos
    • , Chi-Hui Liang
    •  & Dennis R. Burton
  2. IAVI Neutralizing Antibody Center, The Scripps Research Institute, La Jolla, California 92037, USA

    • Devin Sok
    • , Khoa M. Le
    • , Karen L. Saye-Francisco
    • , Joseph G. Jardine
    • , Jennifer Ruiz
    • , Alejandra Ramos
    • , Chi-Hui Liang
    • , Ian A. Wilson
    • , Andrew B. Ward
    •  & Dennis R. Burton
  3. Center for HIV/AIDS Vaccine Immunology and Immunogen Discovery, The Scripps Research Institute, La Jolla, California 92037, USA

    • Devin Sok
    • , Khoa M. Le
    • , Karen L. Saye-Francisco
    • , Joseph G. Jardine
    • , Jennifer Ruiz
    • , Alejandra Ramos
    • , Chi-Hui Liang
    • , Ian A. Wilson
    • , Andrew B. Ward
    •  & Dennis R. Burton
  4. International AIDS Vaccine Initiative, New York, New York 10004, USA

    • Devin Sok
    • , Khoa M. Le
    • , Jennifer Ruiz
    •  & Alejandra Ramos
  5. Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California 92037, USA

    • Melissa Vadnais
    •  & Vaughn V. Smider
  6. Department of Integrative Structural and Computational Biology, The Scripps Research Institute, La Jolla, California 92037, USA

    • Jonathan L. Torres
    • , Zachary T. Berndsen
    • , Leopold Kong
    • , Robyn Stanfield
    • , Ian A. Wilson
    •  & Andrew B. Ward
  7. Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas 77843, USA

    • Patricia L. Chen
    •  & Michael F. Criscitiello
  8. Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medical, Kansas State University, Manhattan, Kansas 66506, USA

    • Waithaka Mwangi
  9. Ragon Institute of MGH, MIT, and Harvard, Cambridge, Massachusetts 02129, USA

    • Dennis R. Burton


  1. Search for Devin Sok in:

  2. Search for Khoa M. Le in:

  3. Search for Melissa Vadnais in:

  4. Search for Karen L. Saye-Francisco in:

  5. Search for Joseph G. Jardine in:

  6. Search for Jonathan L. Torres in:

  7. Search for Zachary T. Berndsen in:

  8. Search for Leopold Kong in:

  9. Search for Robyn Stanfield in:

  10. Search for Jennifer Ruiz in:

  11. Search for Alejandra Ramos in:

  12. Search for Chi-Hui Liang in:

  13. Search for Patricia L. Chen in:

  14. Search for Michael F. Criscitiello in:

  15. Search for Waithaka Mwangi in:

  16. Search for Ian A. Wilson in:

  17. Search for Andrew B. Ward in:

  18. Search for Vaughn V. Smider in:

  19. Search for Dennis R. Burton in:


D.S., K.M.L., J.R. and A.R. performed antigen B cell sorts. K.M.L., J.R. and A.R. performed PCR and antibody cloning, expression, and purification. K.L.S.-F., K.M.L. and J.R. performed neutralization and mutagenesis experiments. M.L.V. and D.S. designed and validated VH and VL gene-specific primers. D.S., K.M.L., M.L.V. and V.V.S. analysed V-region sequences. L.K. and I.A.W. provided protein for immunization experiments. J.L.T., Z.T.B., R.S., A.B.W. and I.A.W. performed structural analysis. J.G.J. performed pH experiments. C.-H.L. performed polyreactivity experiments. P.L.C., M.F.C. and W.M. performed cow immunization and serum ELISA experiments. P.L.C., M.F.C., W.M. and M.L.V. processed lymphocytes and produced mRNA and cDNA. D.S., V.V.S. and D.R.B. helped design and oversaw experiments. D.S., V.V.S. and D.R.B. wrote the manuscript.

Competing interests

D.S., D.R.B. and V.V.S. are inventors on a patent describing the NC-Cow antibodies: US provisional application filed on 14 July 2017.

Corresponding authors

Correspondence to Vaughn V. Smider or Dennis R. Burton.

Reviewer Information Nature thanks J. Mascola and the other anonymous reviewer(s) for their contribution to the peer review of this work.

Publisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Extended data

Supplementary information

PDF files

  1. 1.

    Supplementary Tables

    This file contains Supplementary Tables 1–3.

About this article

Publication history






Further reading


By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.