Preplacodal Ectoderm Cells (PPE)

Preplacodal ecotderm cells are precursors that give rise to all sensory placodes, including lens, olfactory, otic, adenohypophysis placodes and epibranchial and trigeminal placodes, which give rise to sensory cranial ganglia. The lens and adenohypophysis are the only non-neurogenic placodes.