In MSGs, ROCK2 inhibition decreased IL-17 production by non–T cells. (A) Representative PSR staining paired with polarized microscopy of labial MSGs showing collagen type I (red) and collagen type III (green) in biopsies before and after treatment with belumosudil. (B) Percentage area of collagen types I and III in labial MSGs (n = 11; Wilcoxon signed-rank test). (C) Representative multiplex immunofluorescence staining for DAPI (blue), CD3 (cyan), CD4 (red), and IL-17 (green) in labial MSGs before and after treatment with belumosudil with close-up view of marked region in yellow. (D) Changes in CD3⁺ T, CD4⁺, IL-17⁺, and Th17 cells after belumosudil treatment (n = 11; Wilcoxon signed-rank test). (E) Representative multiplex immunofluorescence staining of DAPI (blue), CD3 (cyan), and CD11b (red) in MSGs before and after treatment with belumosudil. (F) Changes in myeloid cells and CD3⁻ IL-17⁺ non–T cells (n = 11; Wilcoxon signed-rank test). P value < .05 is considered significant. Scale bar of 100 μm was used.