CRTAC1 and COVID-19: Based on our finding that the highest direct correlation of CRTAC1 concentration is with IBAQ values for CFP (Figure 4c) and the identification by Huttlin et al. of a CRTAC1‐CFP interaction in a global screen of protein–protein interactions (Huttlin et al., 2021), we evaluated the hypothesis that plasma CRTAC1 is consumed along with plasma CFP during the intense activation of the alternate complement pathway that accompanies severe COVID‐19 ((Boussier et al., 2022; Siggins et al., 2023) and references therein).