CD4 and hydrops fetalis: In human CD4+ AT2R+ T cells, the frequency of FoxP3-positive cells was increased by 2.1-fold (Fig.2, P < 0.0001), the frequency of IL-10-secreting cells was increased by 12.6-fold (healthy donors) and 41.2-fold (HF) compared to CD4+ AT2R− T cells (P < 0.01, P < 0.05, respectively; Fig.2B and C).