CD4 and Zika virus infectious disease: For example, uniquely in acute ZIKV infection, we observed negative correlations between the frequency of ABCs and CD4+ regulatory T cells (Tregs) (r = −0.86, p_adj = 0.002) and between CD69+ CD56dim NK cells and Helios+ Vδ2- γδ T cells (r = −0.77, p_adj = 0.03; Figure 3E).