The damage of the brain parenchyma, as well as the stroke-induced dysfunction of the blood-brain-barrier can make previously hidden CNS antigens "visible", and can thus lead to the development of autoimmune mechanisms.

It seems plausible that stroke-associated immunodepression influences the development and the phenotype of these autoreactive immune responses.

This study will investigate whether cerebral ischemia leads to changes in the immune response, in particular to the development and/or proliferation of autoreactive effector T-cells and/or regulatory T-cells. Furthermore, the association between the severity and the phenotype of this autoimmune response and the clinical course, i.e. prognosis and mortality, will be investigated.

Inclusion Criteria:

• acute media infarct or intracerebral bleeding within the last 36 h (patients)
• NIHSS > 7 (patients)
• age > 17 years (patients), age > 54 years (controls)
• informed consent of patient or legal representative/ of control
• cardiovascular risk such as diabetes mellitus (control)

Exclusion Criteria:

• infections (patients, controls)
• antibiotic or immunosuppressive treatment within the last 4 weeks (patients)
• other CNS disorders

acute media infarct or intracerebral bleeding