Fig 1: Calcitriol facilitated the polarization of Th cells towards the Th2 phenotype while inhibiting the polarization of Th cells towards the Th17 phenotype in an inflammatory environment. A, CFSE-based flow cytometry was used to assess the proliferation of Th2 cells (IL-4 labelled) in the indirect co-incubation (transwell) system. B, CFSE-based flow cytometry was used to assess the proliferation of Th17 cells (IL-17 labelled) in the indirect co-incubation (transwell) system. C, Representative flow cytometry plots of CD4+/IL-4+ Th2 and CD4+/IL-17+ Th17 cells following incubations in various conditions (LPS group, LPS + DC group and LPS + DC + Cal group). D, Quantification of the proportions of CD4+/IL-4+ Th2 and CD4+/IL-17+ Th17 cells (calculated by flow cytometry) and the Th2/Th17 ratio. E, mRNA levels of Th2 polarization-related markers (GATA3, STAT5 and IL-4) in Th cells following incubations in various conditions (LPS group, LPS + DC group and LPS + DC + Cal group). F, Protein levels of Th2 polarization-related markers (p-GATA3, STAT5 and IL-4) in Th cells (determined by Western blotting) following incubations in various conditions (left panel) and semi-quantitative analysis of the protein expression levels (normalized to the level of actin) in terms of the relative grey density (right panel). G, The mRNA levels of Th17 polarization-related markers (STAT3, ROR?T and IL-17) in Th cells following incubations in various conditions (LPS group, LPS + DC group and LPS + DC + Cal group). H, The protein levels of Th17 polarization-related markers (p-STAT3, ROR?T and IL-17) in Th cells (determined by Western blotting) following incubations in various conditions (left panel) and semi-quantitative analysis of the protein expression levels (normalized to the level of actin) in terms of the relative grey density (right panel). The data are shown as the mean ± SD; *P < .05 and **P < .01 represent significant differences between the indicated columns