Local Leukocyte Invasion during Hyperacute Human Ischemic Stroke.

Area of Science:

• Neurology
• Immunology
• Vascular Biology

Background:

• Assessing inflammation in acute ischemic stroke is vital for developing new treatments.
• Understanding immune cell involvement during the hyperacute stage can bridge experimental findings with clinical realities.

Purpose of the Study:

• To investigate the presence and role of immune cells and inflammatory markers in the ischemic blood of patients during the hyperacute stage of ischemic stroke.
• To correlate immune cell accumulation with clinical outcomes.

Main Methods:

• Prospective observation of 151 ischemic stroke patients undergoing mechanical thrombectomy.
• Microcatheter aspiration of arterial blood samples from occluded and normal flow areas.
• Laboratory analysis of leukocytes, platelets, and 13 proinflammatory chemokines/cytokines.

Main Results:

• Leukocyte count significantly increased in occluded vessels, primarily due to neutrophils, lymphocytes, and monocytes.
• Elevated plasma levels of the T-cell chemoattractant CXCL-11 were observed.
• Neutrophil accumulation was negatively associated with short-term clinical outcome (NIHSS at 72 hours).

Conclusions:

• Direct human evidence shows immune cell accumulation (neutrophils, lymphocytes, monocytes) and chemokine upregulation in ischemic vasculature during hyperacute stroke.
• These findings support experimental data on immune cell contribution to ischemic brain damage.
• Ischemic inflammation begins during the vascular occlusion phase, impacting stroke outcomes.