PLoS ONE (Jan 2021)

Presence of antibody-dependent cellular cytotoxicity (ADCC) against SARS-CoV-2 in COVID-19 plasma.

  • For Yue Tso,
  • Salum J Lidenge,
  • Lisa K Poppe,
  • Phoebe B Peña,
  • Sara R Privatt,
  • Sydney J Bennett,
  • John R Ngowi,
  • Julius Mwaiselage,
  • Michael Belshan,
  • Jacob A Siedlik,
  • Morgan A Raine,
  • Juan B Ochoa,
  • Julia Garcia-Diaz,
  • Bobby Nossaman,
  • Lyndsey Buckner,
  • W Mark Roberts,
  • Matthew J Dean,
  • Augusto C Ochoa,
  • John T West,
  • Charles Wood

DOI
https://doi.org/10.1371/journal.pone.0247640
Journal volume & issue
Vol. 16, no. 3
p. e0247640

Abstract

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BackgroundNeutralizing-antibody (nAb) is the major focus of most ongoing COVID-19 vaccine trials. However, nAb response against SARS-CoV-2, when present, decays rapidly. Given the myriad roles of antibodies in immune responses, it is possible that antibodies could also mediate protection against SARS-CoV-2 via effector mechanisms such as antibody-dependent cellular cytotoxicity (ADCC), which we sought to explore here.MethodsPlasma of 3 uninfected controls and 20 subjects exposed to, or recovering from, SARS-CoV-2 infection were collected from U.S. and sub-Saharan Africa. Immunofluorescence assay was used to detect the presence of SARS-CoV-2 specific IgG antibodies in the plasma samples. SARS-CoV-2 specific neutralizing capability of these plasmas was assessed with SARS-CoV-2 spike pseudotyped virus. ADCC activity was assessed with a calcein release assay.ResultsSARS-CoV-2 specific IgG antibodies were detected in all COVID-19 subjects studied. All but three COVID-19 subjects contained nAb at high potency (>80% neutralization). Plasma from 19/20 of COVID-19 subjects also demonstrated strong ADCC activity against SARS-CoV-2 spike glycoprotein, including two individuals without nAb against SARS-CoV-2.ConclusionBoth neutralizing and non-neutralizing COVID-19 plasmas can mediate ADCC. Our findings argue that evaluation of potential vaccines against SARS-CoV-2 should include investigation of the magnitude and durability of ADCC, in addition to nAb.