Fig. 6.

IPA treatment enhances the suppressive function of MDSCs and attenuates disease severity in ESS mice. a, b Immunized ESS mice were treated with PBS vehicle or IPA for 8 weeks, and the disease pathology, including salivary function (a) and autoantibodies against M3R and SSA (b), was assessed (n = 6). c, d ESS mice 20 weeks post-immunization were treated with PBS vehicle or IPA for 8 weeks. The histopathological changes in SGs, including tissue damage and infiltrating CD4⁺ T cells and B cells, were visualized, and the histological scores and infiltrated areas were evaluated. e, f Representative phenotypic analyses of Th1, Th17, Tfh, and plasma cells in the spleens are shown, and the numbers are summarized (n = 6). g Representative flow cytometric analysis of splenic PMN-MDSCs from ESS mice treated with PBS or IPA. h, i Splenic MDSCs from ESS mice were sorting-purified and cocultured with CFSE-labeled CD4⁺ T cells (T-cell/MDSC ratio of 2:1) for 3 days, and T-cell proliferation was assessed by flow cytometry (h). The inhibition rate was deduced (i). Data were derived from at least three independent experiments. Data were presented as the mean ± SD. *P < 0.05, **P < 0.01, and ***P < 0.001