 The cell populations exhibiting neuronal differentiation are believed to secrete surface glycoproteins and glycolipids which mediate cell-to-cell recognition and adhesion.One hypothesis is that these sticky cell surface markers cause the developing cell bodies to cluster or aggregate and their primitive neurites to tangle.As the cells grow, the neurite tangle remains centrally located and the cell bodies are squeezed to the periphery, thus explaining the rosette pattern.