This one-dimensional Th1/Th2 paradigm can, however, not fully explain the immunological changes observed during preeclampsia and recent work has expanded the dichotomy to include the Th17 phenotype and a subset of CD4+ T cells known as CD25+ Forkhead box P3 gene (Foxp3+) Tregs (128). This evidence concerns the gene CD4 and preeclampsia.