OBJECTIVES/GOALS: In this work investigating the epidemiological differences associated with Post Acute Sequelae of SARS-CoV-2(PASC) patho genesis we willassess the sex differences inocular viral persistence and the immunologic profile in tear film obtained from COVID-19 patients. METHODS/STUDY POPULATION: Participants will be enrolled from the NIH funded RECOVER Consortium at the 15 adult hubs in the US and will include those with acute COVID-19 (n=250), followed up at baselineto 48 weeks post infection. RT-PCR will be used to detect viral RNA and electro chemiluminescence assays will be used to detect IgG, IgA1 and IgA2 antibodies.Tear film antibody titers will be measured longitudinally in all participants to assess the kinetics of the immune responses in those who developed PASC and those who did not. Tear film antibody titers will be correlated with antibody titers in the blood and compared between those individuals with or without measurable viral RNA in tear film. RESULTS/ANTICIPATED RESULTS: Logistic regression models will be used assess the association of viral persistence with PASC status controlling for relevant covariates. Linear mixed regression models will be used to assess the association of IgA1/IgA2 with PASC status. We expect to observe delayed clearance of viral RNA and elevation in SARS-CoV-2 specific IgA2/IgA1 in the tear film of patients with PASC compared with those without PASC. Given evidence of increased PASC risk in women we expect to observe higher rates of SARS-CoV-2 ocular viral persistence and higher SARS-CoV-2 specific IgA2/IgA1 ratios in women with COVID-19 when compared to men with COVID-19. DISCUSSION/SIGNIFICANCE: There is concern that PASC will pose a major global health challenge given the scale of the Covid-19 pandemicand the patho genesis remains unclear. This work is highly likely to improve our understanding of the mechanisms of PASC and the reasons why women are more vulnerable to this condition.