Unsupervised clustering methods demonstrated a different population composition between CD66+CD15+ LDGs and CD66+CD15+ PMNs during acute COVID-19, where PMNs mainly consisted of CD16+/CD11b+ (cluster #3) and CD16+/CD11b-/low (cluster #4) (mild cases in Fig 6A and 6B and 6C and severe cases in S4A and S4B Fig; individual patients are shown in S4C and S4D Fig). This evidence concerns the gene FUT4 and COVID-19.