OBJECTIVES/GOALS: The study aims to explore the role of microglial behavior in cognitive impairment associated with vascular dementia (VaD) and long COVID. Using immunohistochemistry (IHC) and quantitative PCR (qPCR), we will assess the expression of Iba-1, a microglial activation marker, in subjects with VaD and SARS-CoV-2 infection. METHODS/STUDY POPULATION: Out of 48 female C57BL/6 mice, 24 had surgical intervention in the form of bilateral carotid artery stenosis (BCAS) for experimental induction of vascular dementia. After 2 weeks, 12 BCAS and 12 non-BCAS were infected with 1E4 PFU of mouse-adapted 10 (MA10) strain of SARS-CoV-2. 2 weeks post-infection, 4 weeks post-operatively, all animals were euthanized and tissues were processed for cDNA and histology. Immunofluorescence and RT-qPCR used to quantify microglia via Iba-1, BBB integrity via claudin-5 as well as occludin, GFAP, and integrin a5. RESULTS/ANTICIPATED RESULTS: We anticipate observing distinct patterns of microglial behavior in subjects with vascular dementia (VaD) and those with long COVID. Through immunohistochemistry (IHC), we expect to see increased Iba-1 expression, indicative of microglial activation. Quantitative PCR (qPCR) will likely corroborate these findings, showing elevated levels of Iba-1 mRNA. Lastly, we anticipate that the data will reveal interactions between microglia and the blood-brain barrier (BBB). These interactions could provide insights into how microglial behavior influences BBB integrity and, consequently, cognitive function in VaD and long COVID. DISCUSSION/SIGNIFICANCE: This study aims to clarify the role of microglia in cognitive decline linked to vascular dementia and long COVID. By categorizing patients based on microglial activation, we can better tailor treatments. The findings could lead to targeted therapies that address cognitive impairment in these conditions.