Fig. 1.

Inflammasome- and pyroptosis-associated genes and proteins are up-regulated in the CNS of MS patients. (A and B) Transcript levels of inflammasome-associated genes were assessed using RT-PCR in MS (n = 14) and non-MS (n = 10) white matter autopsy samples. Values represent relative fold change compared with non-MS controls, with threshold cycles normalized to GAPDH (Mann–Whitney U test). (C–F) White matter was immunostained for proteins of interest, including MHC class II (C), IL-1β (D), caspase-1 (E), and GSDMD (F). (Magnification, 40×.) GSDMD immunoreactivity was localized to the plasma membrane of cells within MS lesions (F, ii, Inset). Arrows indicate positive cells. “D” indicates the area of demyelination. (G) Immunofluorescent labeling of macrophages/microglia in MS white matter with GSDMD (red), Iba-1 (green), and DAPI (blue) demonstrated GSDMD expression in Iba-1⁺ cells. (H) Immunofluorescent labeling of ODCs in MS white matter with GSDMD (red), GST-pi (green), and DAPI (blue) demonstrated GSDMD expression in GST-pi⁺ cells. (Scale bars in G and H, 13 μm.) (I) The number of IL-1β⁺, caspase-1⁺, and GSDMD⁺ cells in white matter was quantified using a minimum of three MS and three non-MS autopsy samples, with a minimum of six nonoverlapping fields of view per patient. Data represent mean cell number per square millimeter ± SEM (Student’s t test). (J) The proportion of GSDMD⁺ microglia and ODCs was quantified. Proportions of microglia were calculated based on a minimum of 150 Iba-1⁺ cells per group, using sections from two or three autopsy samples. Proportions of ODCs were calculated based on a minimum of 400 GST-pi⁺ cells per group, using sections from two or three autopsy samples (χ² test). *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001.