Ischemic stroke is a leading cause of death and disability, for which treatment options are very limited. The therapeutic dilemma created by the opposing goals of achieving rapid reperfusion and preventing intracerebral hemorrhage (ICH), has led us to consider the utility of targeting an inflammatory paradigm, the complement cascade, for inhibition in ischemic stroke. Studies are driven by the hypothesis that complement activation contributes directly to cerebral injury in stroke and may indirectly reduce the efficacy of tPA due to plasmin-dependent activation of complement. Preliminary data in a model of stroke using gene deficient mice have pointed to the critical deleterious role for leukocyte recruitment via the P- and E-selectin and ICAM-1 glycoprotein adhesion receptors. More recently, we have shown that ischemia triggers neurons to express an early complement component (C1q, thereby potentially flagging themselves for lysis or receptor mediated immune clearance. C1q-expressing, ischemically injured neurons bind a soluble truncated form of the extracellular domain of the complement receptor 1 (sCR1), which inhibits local complement activation and confers partial cerebral protection in stroke. When this complement-inhibitory protein is covalently modified by sLex- glycosylation to additionally inhibit selectin-mediated events, striking gains are observed in terms of reducing leukocyte and platelet recruitment, leading to a safe, durable protection even with delayed treatment. Preliminary data in our new primate (baboon) model of reperfused stroke demonstrate similar upregulation of cerebral microvascular selectin and neuronal C1q expression in the ischemic zone. In a double-blind placebo-controlled trial of baboon stroke we have just completed, a humanized anti-P-/E-selectin antibody demonstrated moderate cerebral protective efficacy. Together, these data lead us to hypothesize that selectin- and complement-mediated immune-inflammatory mechanisms are pathophysiologically relevant in stroke, and that simultaneous inhibition of both mechanisms may provide a novel and useful therapeutic target. Furthermore, given that plasmin may activate complement, and anti-complement approach might be especially useful in stroke to increase the efficacy of and therapeutic window for rtPA. These data lead directly to the Specific Aims, which are: (1) demonstrate the role of C1q expression in murine stroke using C1qa -/- mice and determine whether the effect of c1q expression is injurious via activation of the complement cascade and/or via local binding of transmembrane and cytosolic receptors leading to enhanced oxidative stress and phagocytosis; (2) determine whether thrombolysis with tPA activates complement, thereby diminishing it's capacity to protect the brain in stroke; and (3) determine the pathophysiological contribution of C1q expression in primate stroke using complement blockade (with sCR1) strategy as well as a combined anti-adhesion receptor, anti-complement strategy (sCR1/SLex).

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS040409-03
Application #
6540307
Study Section
Special Emphasis Panel (ZRG1-BDCN-3 (01))
Program Officer
Jacobs, Tom P
Project Start
2000-09-30
Project End
2005-06-30
Budget Start
2002-07-01
Budget End
2003-06-30
Support Year
3
Fiscal Year
2002
Total Cost
$389,776
Indirect Cost
Name
Columbia University (N.Y.)
Department
Neurosurgery
Type
Schools of Medicine
DUNS #
167204994
City
New York
State
NY
Country
United States
Zip Code
10032
Ducruet, Andrew F; Zacharia, Brad E; Sosunov, Sergey A et al. (2012) Complement inhibition promotes endogenous neurogenesis and sustained anti-inflammatory neuroprotection following reperfused stroke. PLoS One 7:e38664
Ducruet, Andrew F; Sosunov, Sergey A; Zacharia, Brad E et al. (2011) The Neuroprotective Effect of Genetic Mannose-binding Lectin Deficiency is not Sustained in the Sub-acute Phase of Stroke. Transl Stroke Res 2:588-599
Gigante, Paul R; Kotchetkov, Ivan S; Kellner, Christopher P et al. (2011) Polymorphisms in complement component 3 (C3F) and complement factor H (Y402H) increase the risk of postoperative neurocognitive dysfunction following carotid endarterectomy. J Neurol Neurosurg Psychiatry 82:247-53
Ducruet, Andrew F; Sosunov, Sergey A; Visovatti, Scott H et al. (2011) Paradoxical exacerbation of neuronal injury in reperfused stroke despite improved blood flow and reduced inflammation in early growth response-1 gene-deleted mice. Neurol Res 33:717-25
Akpan, Nsikan; Serrano-Saiz, Esther; Zacharia, Brad E et al. (2011) Intranasal delivery of caspase-9 inhibitor reduces caspase-6-dependent axon/neuron loss and improves neurological function after stroke. J Neurosci 31:8894-904
Kellner, Christopher P; Connolly Jr, E Sander (2010) Neuroprotective strategies for intracerebral hemorrhage: trials and translation. Stroke 41:S99-102
Hanafy, Khalid A; Morgan Stuart, R; Fernandez, Luis et al. (2010) Cerebral inflammatory response and predictors of admission clinical grade after aneurysmal subarachnoid hemorrhage. J Clin Neurosci 17:22-5
Starke, Robert M; Komotar, Ricardo J; Otten, Marc L et al. (2009) Adjuvant embolization with N-butyl cyanoacrylate in the treatment of cerebral arteriovenous malformations: outcomes, complications, and predictors of neurologic deficits. Stroke 40:2783-90
Hassid, Benjamin G; Nair, M Nathan; Ducruet, Andrew F et al. (2009) Neuronal RAGE expression modulates severity of injury following transient focal cerebral ischemia. J Clin Neurosci 16:302-6
Garrett, Matthew C; Otten, Marc L; Starke, Robert M et al. (2009) Synergistic neuroprotective effects of C3a and C5a receptor blockade following intracerebral hemorrhage. Brain Res 1298:171-7

Showing the most recent 10 out of 28 publications