The Role of Complement C3a Receptor in Stroke

  • Saif AhmadEmail author
  • Kanchan Bhatia
  • Adam Kindelin
  • Andrew F. DucruetEmail author
Review Paper


The complement system is a key regulator of the innate immune response against diseased tissue that functions across multiple organ systems. Dysregulation of complement contributes to the pathogenesis of a number of neurological diseases including stroke. The C3a anaphylatoxin, via its cognate C3a receptor (C3aR), mediates inflammation by promoting breakdown of the blood–brain barrier and the massive infiltration of leukocytes into ischemic brain in experimental stroke models. Studies utilizing complement deficient mice as well as pharmacologic C3aR antagonists have shown a reduction in tissue injury and mortality in murine stroke models. The development of tissue-specific C3aR knockout mice and more specific C3aR antagonists is warranted to facilitate our understanding of the role of the C3aR in brain ischemia with the ultimate goal of clinical translation of therapies targeting C3aR in stroke patients.


Complement cascade Central nervous system Stroke C3a receptor C3a receptor antagonist 



Research in the authors’s lab is funded by the Barrow Neurological Foundation. The authors thank the staff of Neuroscience Publications at Barrow Neurological Institute for assistance with figure preparation. We thank to Ms. Tasha Mohseni for her editorial assistance with manuscript.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Authors and Affiliations

  1. 1.Department of Neurosurgery, Barrow Neurological InstituteSt. Joseph’s Hospital and Medical Center (SJHMC), Dignity HealthPhoenixUSA
  2. 2.School of Mathematical and Natural SciencesArizona State UniversityPhoenixUSA

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