CD19 and COVID-19: Complementary analysis of cell phenotype along the timeline kinetics, according to days of symptom onset at admission, indicated that patients with COVID-19 symptoms between 3 and 10 days after admission to the study presented an overall decrease in cell phenotypes and their subsets (CD3+, CD19+, CD4+ and CD8+), with a peak at D7, while patients with symptoms between 11 and 24 days after admission to the study presented a progressive increase in these cell phenotypes mainly at D7 and D14–28 time points, with a peak at D7 for the CD19+ phenotype (Figure S4A,B).