Conversely, extracellular matrix (ECM) proteins, such as ECM1, LUM, and immunoregulatory factors (e.g. AHSG, A2M Rehman et al., 2013, and HRG Wakabayashi, 2013) and proteins involved in lipid metabolism (e.g., APOC1, APOD, APOM, GPLD1, and PON1), and negative APPs (e.g., ITIH1, Figure 3C), which are downregulated in severe COVID-19 (Figure S6, summarized in Figure 5), increased over time, approaching the baseline. Here, APOC1 is linked to COVID-19.