CD4+ T cells aggravate hemorrhagic brain injury

Sci Adv. 2023 Jun 9;9(23):eabq0712. doi: 10.1126/sciadv.abq0712. Epub 2023 Jun 7.

Abstract

Leukocyte infiltration accelerates brain injury following intracerebral hemorrhage (ICH). Yet, the involvement of T lymphocytes in this process has not been fully elucidated. Here, we report that CD4+ T cells accumulate in the perihematomal regions in the brains of patients with ICH and ICH mouse models. T cells activation in the ICH brain is concurrent with the course of perihematomal edema (PHE) development, and depletion of CD4+ T cells reduced PHE volumes and improved neurological deficits in ICH mice. Single-cell transcriptomic analysis revealed that brain-infiltrating T cells exhibited enhanced proinflammatory and proapoptotic signatures. Consequently, CD4+ T cells disrupt the blood-brain barrier integrity and promote PHE progression through interleukin-17 release; furthermore, the TRAIL-expressing CD4+ T cells engage DR5 to trigger endothelial death. Recognition of T cell contribution to ICH-induced neural injury is instrumental for designing immunomodulatory therapies for this dreadful disease.

MeSH terms

  • Animals
  • Brain / metabolism
  • Brain Injuries* / etiology
  • Brain Injuries* / metabolism
  • CD4-Positive T-Lymphocytes / metabolism
  • Cerebral Hemorrhage / etiology
  • Cerebral Hemorrhage / metabolism
  • Disease Models, Animal
  • Mice
  • T-Lymphocytes* / metabolism