Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jan-Dec;13(1):1893426.
doi: 10.1080/19420862.2021.1893426.

Bispecific VH/Fab antibodies targeting neutralizing and non-neutralizing Spike epitopes demonstrate enhanced potency against SARS-CoV-2

Shion A Lim  1 , Josef A Gramespacher  1 , Katarina Pance  1 , Nicholas J Rettko  1 , Paige Solomon  1 , Jing Jin  2 , Irene Lui  1 , Susanna K Elledge  1 , Jia Liu  1 , Colton J Bracken  1 , Graham Simmons  2 , Xin X Zhou  1 , Kevin K Leung  1 , James A Wells  1   3   4
Affiliations

Bispecific VH/Fab antibodies targeting neutralizing and non-neutralizing Spike epitopes demonstrate enhanced potency against SARS-CoV-2

Shion A Lim et al. MAbs. 2021 Jan-Dec.

Abstract

Numerous neutralizing antibodies that target SARS-CoV-2 have been reported, and most directly block binding of the viral Spike receptor-binding domain (RBD) to angiotensin-converting enzyme II (ACE2). Here, we deliberately exploit non-neutralizing RBD antibodies, showing they can dramatically assist in neutralization when linked to neutralizing binders. We identified antigen-binding fragments (Fabs) by phage display that bind RBD, but do not block ACE2 or neutralize virus as IgGs. When these non-neutralizing Fabs were assembled into bispecific VH/Fab IgGs with a neutralizing VH domain, we observed a ~ 25-fold potency improvement in neutralizing SARS-CoV-2 compared to the mono-specific bi-valent VH-Fc alone or the cocktail of the VH-Fc and IgG. This effect was epitope-dependent, reflecting the unique geometry of the bispecific antibody toward Spike. Our results show that a bispecific antibody that combines both neutralizing and non-neutralizing epitopes on Spike-RBD is a promising and rapid engineering strategy to improve the potency of SARS-CoV-2 antibodies.

Keywords: Bispecific; COVID-19; SARS-CoV-2; knob-in-hole; neutralizing antibody.

PubMed Disclaimer

Figures

Figure 1.
Figure 1.
Fabs identified by phage display bind Spike RBD and Secto with high affinity outside of the ACE2 binding site
Figure 2.
Figure 2.
Bispecific VH/Fab IgGs bind with high affinity to trimeric Secto. (a) Cartoon schematic of the bispecific VH/Fab IgG antibody scaffold utilized in this study. (b-e) Multipoint BLI measurements (10 nM, 5 nM, and 2.5 nM) of the indicated bispecific antibody on Secto. (b) Bis1 (VH A01/FabC01) (c) Bis2 (VH B01/FabC01) (d) Bis3 (VH A01/FabD01) (e) Bis4 (VH B01/FabD01)
Figure 3.
Figure 3.
Bispecific VH/Fab IgGs are more potent in neutralizing SARS-CoV-2 pseudovirus than the mono-specific counterparts
Figure 4.
Figure 4.
Bispecific VH/Fab IgGs neutralize authentic SARS-CoV-2 virus more potently than the mono-specific VH-Fcs
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Grein J, Ohmagari N, Shin D, Diaz G, Asperges E, Castagna A, Feldt T, Green G, Green ML, Lescure FX, et al. Compassionate use of remdesivir for patients with severe Covid-19. N Engl J Med. 2020;382:2327–10. doi:10.1056/NEJMoa2007016. - DOI - PMC - PubMed
    1. Joyner MJ, Senefeld JW, Klassen SA, Mills JR, Johnson PW, Theel ES, Wiggins CC, Bruno KA, Klompas AM, Kunze KL, et al. Effect of convalescent plasma on mortality among hospitalized patients with COVID-19: initial three-2 month experience. medRxiv. 2020. doi:10.1101/2020.08.12.20169359. - DOI
    1. Chan KK, Dorosky D, Sharma P, Abbasi SA, Dye JM, Kranz DM, Herbert AS, Procko E.. Engineering human ACE2 to optimize binding to the spike protein of SARS coronavirus 2. Science. 2020;1265:eabc0870. - PMC - PubMed
    1. Monteil V, Kwon H, Prado P, Hagelkruys A, Wimmer R, Stahl M, Leopoldi A, Garreta E. Inhibition of SARS-CoV-2 infections in engineered human tissues using clinical-grade soluble human ACE2. Cell. 2020;181:905–13. - PMC - PubMed
    1. Glasgow A, Glasgow J, Limonta D, Solomon P, Lui I, Zhang Y, Nix MA, Rettko NJ, Lim SA, Zha S, et al. Engineered ACE2 receptor traps potently neutralize SARS-CoV-2. Proc Natl Acad Sci USA. 2020;117:28046–55. doi:10.1073/pnas.2016093117. - DOI - PMC - PubMed

Publication types

MeSH terms