Abstract T P182: Peripheral Immune Protein Profiles Can Differentiate Ischemic Stroke from Transient Ischemic Attack and are Correlated with Stroke Severity

Abstract

Introduction: Inflammatory signals released from ischemic brain tissue recruits peripheral immune cells to the brain following ischemic stroke (IS). The mechanisms behind this crosstalk between the brain and periphery are not well understood. Studies suggest that excessive T-cell activation and migration into the brain may contribute to a greater infarct volume and increased stroke severity. The goal of the project was to evaluate the protein expression of a variety of T cell related cytokines in the peripheral blood to determine their differential expression in ischemic stroke (IS) and transient ischemic attack (TIA). Methods: Blood was drawn from IS and TIA patients within 24 hours of last known normal. Serum was processed from whole blood centrifuged within one hour of collection then frozen at -80C until analysis. Serum cytokine concentrations of 35 analytes were quantified using a Multi-Analyte Profiling Kit (R&D Systems®) on the Luminex® 100 platform. Random forest methodology and logistic regression were used to identify cytokines and demographic characteristics that distinguish stroke from TIA. Univariate analyses were performed to describe relationships between cytokine levels and NIHSS. Results: We analyzed data from n=17 IS and n=12 TIA patients, with an average age of 69 years and a median NIHSS of 3. Age, NIHSS, dyslipidemia, CD40, and CD27 were identified as important predictors of stroke versus TIA (Error rate = 0.233, sensitivity =0.765, specificity = 0.769). In IS patients CD27 and CD40 were significantly correlated with NIHSS (r=0.823, p=0.006; r=0.66; p=0.03 respectively). Conclusion: The peripheral blood protein expression of CD27 and CD40 correlates with stroke severity, and in combination with demographic data may be used to differentiate IS from TIA in the acute care setting. Future studies are needed to assess the functional role of CD27 and CD40 following stroke for potential therapeutic applications.