Importance of T lymphocytes in brain injury, immunodeficiency, and recovery after cerebral ischemia

Vanessa H Brait, Thiruma V Arumugam, Grant R Drummond, Christopher G Sobey

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163 Citations (Scopus)


Following an ischemic stroke, T lymphocytes become activated, infiltrate the brain, and appear to release cytokines and reactive oxygen species to contribute to early inflammation and brain injury. However, some subsets of T lymphocytes may be beneficial even in the early stages after a stroke, and recent evidence suggests that T lymphocytes can also contribute to the repair and regeneration of the brain at later stages. In the hours to days after stroke, T-lymphocyte numbers are then reduced in the blood and in secondary lymphoid organs as part of a stroke-induced immunodeficiency syndrome, which is mediated by hyperactivity of the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis, resulting in increased risk of infectious complications. Whether or not poststroke T-lymphocyte activation occurs via an antigen-independent process, as opposed to a classical antigen-dependent process, is still controversial. Although considerable recent progress has been made, a better understanding of the roles of the different T-lymphocyte subpopulations and their temporal profile of damage versus repair will help to clarify whether T-lymphocyte targeting may be a viable poststroke therapy for clinical use.
Original languageEnglish
Pages (from-to)598 - 611
Number of pages14
JournalJournal of Cerebral Blood Flow and Metabolism
Issue number4
Publication statusPublished - 2012

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