A tetrameric ACE2 protein broadly neutralizes SARS-CoV-2 spike variants of concern with elevated potency. - Leach, Adam; Ilca, F. Tudor; Akbar, Zulaikha; Ferrari, Mathieu; Bentley, Emma M.; Mattiuzzo, Giada; Onuoha, Shimobi; Miller, Ami; Ali, Hanif; Rabbitts, Terence H. (Antiviral Research, 2021)