CD4 and Hypertension: The memory T-cell populations that were markedly elevated in the peripheral blood of patients with hypertension were CD4 TEM cells [percentage: HTN vs. NC, 0.21 vs. 0.12, respectively; p = 2.9*10−7], CD8 TEM cells [percentage: HTN vs. NC, 0.86 vs. 0.74, respectively; p = 0], and CD8 TCM cells [percentage: HTN vs. NC, 0.02 vs. 0.006, respectively; p = 0.00027] (Figure 2A).