Neuronal Protection in Stroke by an sLe x -Glycosylated Complement Inhibitory Protein

Abstract

Glycoprotein adhesion receptors such as selectins contribute to tissue injury in stroke. Ischemic neurons strongly expressed C1q, which may target them for complement-mediated attack or C1qRp-mediated clearance. A hybrid molecule was used to simultaneously inhibit both complement activation and selectin-mediated adhesion. The extracellular domain of soluble complement receptor–1 (sCR1) was sialyl Lewis x glycosylated (sCR1sLe^x) to inhibit complement activation and endothelial-platelet-leukocyte interactions. sCR1 and sCR1sLe^xcolocalized to ischemic cerebral microvessels and C1q-expressing neurons, inhibited neutrophil and platelet accumulation, and reduced cerebral infarct volumes. Additional benefit was conferred by sialyl Lewis x glycosylation of the unmodified parent sCR1 molecule.