SMAD2 and hydrops fetalis: Of interest, it has been shown that low doses of HF selectively inhibited the differentiation of the proinflammatory T helper 17 murine and human cells (TH17 cells) by activating a cytoprotective signaling pathway, without directly modulating TGFβ-induced SMAD2 phosphorylation or other lymphocytes responses to TGFβ [41].