Localization of the CD15-epitope in the inner ear of the developing mouse

The expression of the 3-fucosyl-N-acetyl-lactosamine (CD15) epitope during the embryonic development of the mouse inner ear has been immunohistochemically studied on paraffin sections from day 8.5 to day 19 of gestation. Consecutive steps of morphological development are accompanied by up- and down-regulation of CD15 expression and changing cell patterns. Expression levels are reduced once structural maturation has been accomplished. Since CD15 has been described as a determinant that is expressed during critical developmental steps, it is speculated that the changes in the epitope expression in the inner ear reflect relevant stages of differentiation. This system may thus serve as a model for understanding inner ear development.