Fig 1: Neuronal polarization of hPDLSCs-derived neural-like cells. (a) hPDLSCs-derived neural-like cells start their development as rounded spheres that initiate neurite outgrowth at a single site on the plasma membrane. (b) These later transform into cells containing several short neurites developed around the cell body. (c) The cytoskeletal network is reorganizated. ß-III tubulin accumulates densely under the cellular membrane of the cell body and in cell neurites while actin microfilaments are mainly found in cell neurites. (d) The peripheral domain in the growth cone of hPDLSCs-derived neural-like cells is composed of radial F-actin bundles and the central domain contains ß-III tubulin microtubules. (e) Micrographs showing that the growth cone also contains filopodia and vesicles on the cell surface. (f) Microtubule-associated proteins Tau and MAP2 were also found in hPDLSCs-derived neural-like cells. At later stages of development, hPDLSCs-derived neural-like cells gradually adopt a complex morphology (g) giving rise to a variety of neuron-like forms (h). (i) Cytoskeletal protein ß-III tubulin and F-actin staining shown that hPDLSCs-derived neural-like cells develop distinct axon-like and dendrite-like processes (numbers locate the areas shown in higher power). The scale bars are 25 µm in the light microscope images, and 10 µm in the scanning electron micrographs. b, actin bundles; f, filopodia; LM, light microscopy; SEM, scanning electron microscopy; v, vesicles.