DNase I–mediated cerebrovascular protection and antihemorrhagic effects after ischemic stroke are abolished by cGAMP. (A) Representative immunoblots for STING, pTBK1 and total TBK1, and pIRF3 and total IRF3 expression in the ischemic cortex of tPA-treated mice after treatment with DNase I or DNase I in combination with cGAMP. (B-D) Quantification of band intensities for each group (n = 5). (E-F) Quantification of IFN-β and IL-6 levels by enzyme-linked immunosorbent assay in the ischemic cortex (n = 6). (G-H) Representative immunoblots and quantification of IgG levels in capillary-depleted brain tissue. (I-J) Quantification of extravascular dextran fluorescence in tPA-treated mice after treatment with DNase I or DNase I in combination with cGAMP. Scale bar, 20 μm. At 24 hours after stroke, mice were administered an intravascular injection of 40 KDa of FITC-labeled dextran, and brain sections were stained with CD31. (K) Representative images of the dorsal surface (upper panel) and a coronal section (bottom panel) show cerebral hemorrhage 24 hours after stroke. (L) Quantification of cerebral hemorrhage (n = 8). (M-O) Effects of DNase I or combination of DNase I and cGAMP on forelimb force test and beam walking test 24 hours after stroke in tPA-treated mice (n = 10). Values are means ± standard deviation. *P < .05. GAPDH, glyceraldehyde-3-phosphate dehydrogenase.