Presence of Langerhans cells in the central corneas of normal human infants.

Nine normal adult and seven normal infant human corneas were studied for the presence of dendritic epithelial Langerhans cells in a masked fashion. Epithelial flatmounts were separated from the underlying corneal stroma using EDTA. The epithelial Langerhans cell densities were determined in the limbus as well as the peripheral, pericentral, and central corneal regions following staining with ATPase. Segments of the flatmounts were also studied by immunofluorescence to confirm that the dendritic cells contained class II histocompatibility antigens. The limbus, peripheral, and pericentral zones of adult and infant flatmounts contained similar densities of Langerhans cells. However, the central corneal Langerhans cell densities in infants were significantly elevated as compared with those in adults. These results suggest that Langerhans cells are a constant constituent of the human central corneal epithelium during late gestation and early infancy. They further suggest that perturbations of the corneal epithelium are not required for the presence of Langerhans cells in the corneal epithelium.