Histogenesis of sensory epithelium in reaggregates of dissociated embryonic chick otocysts

Abstract

Embryonic chick otocysts with the associated mesenchyme and acoustic ganglion, cultivated in organ culture, developed completely differentiated sensory epithelial membranes of the inner ear such as the organ of Corti and cristae.

Otocysts with the associated mesenchyme and acoustic ganglion (and occasionally brain wall), enzymatically dissociated into cellular suspensions, reaggregated into clumps of cells that developed into a histological product of epithelium-lined structures, cartilage, connective tissue, differentiated ganglion cells and central nerve tissue.

Areas of reconstituted epithelium, supported by mesenchyme, differentiated into sensory epithelial membranes composed of hair cells and supporting cells. Morphologically these membranes could not be classified as membranes of the organ of Corti and cristae.

Certain observations described in this paper indicated that proximity of mesenchymal and epithelial tissue were essential for the histo-differentiation of the epithelium of the otocyst into sensory areas; however, complete cytodifferentiation of hair cells was indicated as being dependent on innervation. These factors are discussed.