Fig. 1

Impact of IL-1Ra on the BBB after LPS+HI exposure. Titer (ELISA) of hrIL-1Ra (pg/mg) in the right cerebral hemisphere at 4 and 24 h after LPS+HI ± IL-1Ra exposure (a). Immunohistochemistry (IHC) staining of hrIL-1Ra associated with neurons (arrowhead) in LPS+HI ± IL-1Ra-exposed brains at 48 h (b). Relative hrIL-1Ra expression (IHC) at 48 h in LPS+HI ± IL-1Ra-exposed frontoparietal cortical areas compared to control (c). IL-1Ra prevented albumin (IHC staining) entry within the brain at 48 h (d). IL-1Ra decreased IHC relative expression of albumin in the right cerebral hemispheres 48 h after LPS+HI exposure (e). IL-1Ra prevented LPS+HI-induced BBB disruption (loss of linear co-localization of GFAP and claudin-5 (arrowheads)) as seen by confocal microscopy following immunofluorescent (IF) staining of claudin-5 and GFAP of blood vessels of right frontoparietal middle neocortical blood vessels of LPS+HI ± IL-1Ra-exposed rats at 4 h post-HI (f). IF images are representative of the blood vessels in damaged areas. Error bars represent means ± SEM, scale bar = 10 μm, three to six animals per conditions, unpaired t test with Welch correction, * p ≤ 0.05, *** p ≤ 0.001, **** p ≤ 0.0001. Abbreviations: GFAP glial fibrillary acidic protein, Clau5 claudin-5