Using RLBAs with full-length ERFL, SNX8 and KDELR1 proteins, we found that all three target proteins were significantly enriched compared with both the at-risk controls (P = 0.00022, P = 3.68 × 10−5 and P = 2.36 × 10−5, respectively) and the patients with severe acute COVID-19 (P = 0.0066, P = 0.00735 and P = 0.00114, respectively; Extended Data Fig. 2d). Here, KDELR1 is linked to COVID-19.