ICH + HG significantly increased number of MPO positive neutrophils (green A) (n = 3 per group), and accumulation of MPO (B-C) (n = 6 per group). While scramble siRNA had no effect, in vivo knock down of integrin-β1 (siRNA) aggravated ICH + HG induced brain infiltration by neutrophils. Intranasal administration of rOPN 3 μg resulted in a decreased number of neutrophils in the brain. C-A1, Coumermycin A1 (A-C). All data are expressed as mean ± SEM, a value of p < 0.05 represents statistical significance. *P < 0.05 vs. sham, #P < 0.05 vs. vehicle, & P < 0.05 vs. Integrin-β1 siRNA, @ P < 0.05 vs. rOPN (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)