Redefining the human corneal immune compartment using dynamic intravital imaging

Significance The corneal immune compartment plays an important role in protecting the eye from disease. Visualization of corneal immune cells has clinical and diagnostic utility. Yet, knowledge of the breadth of immune cell types in the human cornea is lacking. By performing non-invasive time-lapse imaging of the cornea in healthy humans, we identify that intraepithelial lymphocytes make up a substantial portion of cells in the epithelium. To date, these T cells have been classified as dendritic cells using static imaging. Our live imaging approach redefines understanding of the human corneal cellular immune landscape. Dynamic analysis reveals how corneal immune cells behave in the steady state and respond to acute and chronic proinflammatory stimuli, enabling rapid evaluation of immune responses in situ.