Journal: The FASEB Journal
Article Title: Autoantibodies targeting angiotensin‐converting enzyme 2 are prevalent and not induced by SARS ‐ CoV ‐2 infection
doi: 10.1096/fj.202402694R
Figure Lengend Snippet: Effect of ACE2 autoantibodies on ACE2 enzymatic activity and SARS‐CoV‐2 spike‐ACE2 binding. (A) ACE2 autoantibodies levels (IgG, IgA, IgM) in a subset of samples for which ACE2 enzymatic activity was assessed. (B) Levels of ACE2 enzymatic activity in individuals who had IgG and/or IgA and/or IgM ACE2 autoantibodies in contrast to the individuals who had no detectable ACE2 autoantibodies. (C) Levels of ACE2 enzymatic activity in individuals who self‐reported a SARS‐CoV‐2 infection and/or had serological markers of previous infection. (D) ACE2 autoantibodies levels in a subset of samples in which ACE2 and spike interaction was assessed. (E) Anti‐Spike IgG antibodies levels pre‐ and post‐depletion in sera. (F) % inhibition representing the ability of the sera to inhibit spike and ACE2 interaction pre‐ and post‐depletion. (G) % inhibition representing the ability of the sera to inhibit spike and ACE2 interaction in individuals who had IgG and/or IgA and/or IgM ACE2 autoantibodies above threshold in contrast to the individuals who had no detectable ACE2 autoantibodies. (H) Linear correlation between the ability of sera to inhibit Spike and ACE2 binding and the levels of Spike IgG antibodies in depleted sera. Unpaired two‐sided Wilcoxon test was used to establish statistical significance where applicable, p ≤ 0.05 (*), p ≤ 0.01 (**), p ≤ 0.001 (***), p ≤ 0.0001 (****).
Article Snippet: 10 μL of neutralized samples was transferred to 96‐well black plates containing 15 μM of fluorogenic ACE2 substrate Mca‐APK(Dnp) (Anaspec, Fremont, CA, USA, cat. AS‐60757), to a final concentration of 11.25 μM.
Techniques: Activity Assay, Binding Assay, Infection, Inhibition