Expression of Lewis Y (Le(y)) antigen in human anagen hair follicles.

Lewis Y (Le(y)) antigen, a difucosylated tetrasaccharide found on type 2 blood group oligosaccharides of glycolipids and glycoproteins, is thought to be a phenotypic marker predictive of cell differentiation. The distribution of this antigen in human anagen hair follicles was examined by immunohistochemical staining using a monoclonal antibody (AH-6) to Le(y). In the bulbar and suprabulbar portion of anagen hair follicles, Le(y) antigen was detected in the three layers of the inner root sheath. Subsequently, the positive staining became translocated to the innermost layer of the outer root sheath in the middle part of the hair follicles. In the upper portion of the hair follicles, Le(y) antigen was found in the outer cells of the outer root sheath. These findings suggested that the expression of Le(y) antigen in the anagen hair follicles was correlated with the processes of keratinization or terminal differentiation.