Figure 5.

Initial T cell concentration as the background immunity of individuals against SARS-CoV-2 and reduces mortality. (a) Positive correlation of T cell's antiviral contribution with initial T cell concentration for mild patients (blue), severe patients (green), survivor group (magenta) and non-survivor group (black). Data points are the means, and error bars are the standard deviations. (b) Positive correlation of inhibition rates of IL-6, D-dimer and high sensitive cardiac troponin (HSCT) with initial T cell concentration for survivor group and non-survivor group. Data points are the means, and error bars are the standard deviations. It is worth mentioning that the three rates of the non-survivor group are all zero and overlap with each other; The inhibition rates of D-dimer and HSCT of the survivor group are closed and overlap with each other. (c) D-dimer dynamics of non-survivors with an increase of initial T cell concentration (T₀) reduces organ damage at the later stage. The Red dashed line is the normal upper limit of the D-dimer [4]. For parameters of the simulation, see Methods. (d) Lymphocyte count decreases with age, and mortality (case fatality rate, CFR) increases with age. Males (dashed line) have higher mortality than females (dotted line).