Fig. 4: LAPTM5 is upregulated and associated with the activation of the STING signaling pathway in macrophages in rosacea.

A–C Analysis of the expression levels of LAPTM5 in skin samples from rosacea patients (GSE65914 and HRA000378) and LL-37-induced rosacea-like mice (GSE147950). D, E Scatter plots showing positive correlation of LAPTM5 expression in rosacea skin (GSE65914) and macrophage marker CD68 (D) and STING (E). F, G IHC of LAPTM5 in skin tissues from healthy controls (HC) and rosacea patients (F). Quantification of staining intensity (IOD/Area) for LAPTM5 in the IHC images of rosacea patients and HC (G). n = 5 for each group. H–J IHC of LAPTM5 in skin tissues from control and LL-37-induced rosacea-like mice (H). Quantification of staining intensity (IOD/Area) for LAPTM5 in the IHC images of LL-37-induced rosacea-like mice and control (I). n = 6 for each group. J Immunoblotting analysis of LAPTM5 protein expression in skin tissue lysates from control and LL-37-induced rosacea-like mice. K Immunofluorescence staining of F4/80 (red) and LAPTM5 (green) in skin sections from LL-37- or H-151-treated mice. Nuclei are stained with DAPI (blue). The merged and zoom-in images highlight co-localization of F4/80 and LAPTM5. Scale bars: 100 µm. L–N Quantification of relative fluorescence intensity for LAPTM5 (L) and F4/80 (M) in skin sections from LL-37- or H-151-treated mice. LAPTM5 and F4/80 colocalization (N), expressed as the percentage of double-positive cells relative to total F4/80-positive cells in three randomly selected fields for each sample. Scale bar: 100 µm, n = 6 for each group. O Immunoblot analysis of STING and LAPTM5 expression in skin tissue lysates from mice treated with LL-37, H-151, or LL-37 plus H-151. P, Q Immunoblot analysis of pSTING, STING, pIRF3, IRF3, pNF-κB p65, NF-κB p65, and LAPTM5 in cell lysates from RAW264.7 and L929 cells exposed to increasing concentrations of LL-37 (0, 1, 2, 4, and 8 µM) for 24 h. Data represent the mean ± SEM, **p < 0.01, ***p < 0.001, ****p < 0.0001. Two-tailed unpaired Student’s t-test or One-way ANOVA with Bonferroni’s post hoc test was used. All results are representative of at least three independent experiments.