SELE and COVID-19: The concentration of s-E-Selectin was significantly reduced at days 3–4 and days 5–8 (P < 0.050 vs. Admission) in severe COVID-19 patients (Fig. 3G), but patients with critical COVID-19 showed a rising pattern in s-E-Selectin values, with a significant difference observed at week 2 (P < 0.050 vs. Admission) (Fig. 3H).