Interestingly, percentage of CD45+ serum EVs showed a significant reduction in mild COVID‐19 patients compared to healthy control but without alterations in their size distribution, suggesting the reduction of CD45+ serum EVs is not due to alterations in certain subsets of particle sizes but the overall actual abundance of CD45+ EVs within total serum EVs (Figure 1B, S1C). Here, PTPRC is linked to COVID-19.