Fig. 1

Acrolein-protein adduct formation in human MS lesions. Serial cryosections from demyelinated human MS lesions were stained against proteolipid protein (PLP), CD68 and acrolein-protein adducts. a Active MS lesion featuring CD68⁺ macrophages/microglia packed in the lesion center. Acrolein-protein adducts can be seen in the lesion. b Mixed active/inactive MS lesion containing CD68⁺ macrophages/microglia at the lesion border that enclose a hypocellular lesion center. Acrolein-protein adducts can be seen in the lesion. c Mixed active/inactive MS lesion with no evidence of acrolein-protein adduct formation. d Immunofluorescence image showing acrolein-protein adducts surrounding individual CD68⁺ macrophages/microglia in an MS lesion. e Acrolein-protein adducts in a perivascular cuff containing CD68⁺ macrophages/microglia. f Acrolein-protein adducts with a cellular morphology co-localized with GFAP immunoreactivity (astrocytes), but not with CD68 (g). Scale bars are 1 mm (a–c), 50 µm (d–g) or 100 µm (f)