Introduction: Cytokine profiles of peripheral blood and cerebrospinal fluid (CSF) are used to predict stroke outcomes. Yet, the cytokine profiles of some patients do not match the predicted outcomes.
Hypothesis: We hypothesize that peripheral blood is not an accurate resource for cytokine profiling because the supply of cytokines in the blood and CSF is unknown. Specifically, we postulate that cytokine profiling from a resource that is local to the stroke site is a more accurate method for predicting stroke outcomes. In this study, we collected thrombi from thrombectomy procedures performed on stroke patients who presented to our university affiliated comprehensive stroke center and examined the presence of TNF-alpha.
Methods: This study was approved by the IRB at our university affiliated comprehensive stroke center. All samples were collected with the consent of the donor. Thrombi were collected from stroke patients that underwent thrombectomies at our university affiliated comprehensive stroke center. Thrombi were placed in a lysis buffer containing protease inhibitors. Thrombi were stored at 4C in the neurointerventional lab for a maximum of 12 hrs. Thrombi were then frozen at -80C for long-term preservation. For controls, blood was collected from healthy volunteers. Blood was allowed to coagulate for 30 mins at room temperature to form a clot. The formed clot was then put in lysis buffer for 1 hr. Thrombi lysis from patients and healthy volunteers were subjected to Western bloting.
Results: A total of 10 patients participated, clots were extracted within 8 hours of stroke onset in all. Ten healthy volunteers served as controls. Western Blot showed that TNF-alpha is detected in clots extracted from stroke patients that underwent thrombectomies, but not in clots formulated from healthy volunteers.
Conclusion: Our results show that it is feasible to extract thrombi for cytokine profiling. TNF-alpha was elevated in thrombectomy-extracted clots and TNF-alpha was not detected in healthy volunteers. Our results suggest that proinflammatory cytokines are within the stroke area and our method is a feasible method for cytokine detection. In future studies, we will correlate cytokine quantity with NIHSS.