Axonal growth regulation of fetal and embryonic stem cell-derived dopaminergic neurons by Netrin-1 and Slits

Stem Cells. 2006 Nov;24(11):2504-13. doi: 10.1634/stemcells.2006-0119. Epub 2006 Jul 13.

Abstract

The physical restoration of dopamine circuits damaged or lost in Parkinson disease by implanting embryonic stem (ES)-derived cells may become a treatment. It is critical to understand responses of ES-derived dopamine (DA) neurons to guidance signals that determine axonal path and targeting. Using a collagen gel culture system, we examined effects of secreted molecules Netrin-1 and Slits on neurite outgrowth of fetal DA neurons and murine ES-differentiated DA neurons. We have previously shown that fetal DA neurons express DCC and Robo1/2 receptors and that Netrin-1 and Slit2 function as an attractant and a repellent for DA neurite outgrowth. In the present study, we observe that both Slit1 and Slit3 repel and inhibit neurite growth of fetal DA neurons. Here, we also demonstrate that ES-differentiated neurons including DA neurons express the Netrin receptor DCC and Slit receptor Robo proteins. In the gel culture system of ES cells, Netrin-1 promoted neurite outgrowth mediated by DCC receptor, and Slit1 and Slit3 were inhibitory for neurite outgrowth through Robo receptors. Slit2 appeared to exert inhibitory as well as repulsive effects in the coculture assay. However, unlike fetal DA neurites, no directed neurite outgrowth was observed in the cocultures of ES-derived DA neurons with Netrin-1-, Slit1-, and Slit3-producing cells. The findings suggest that ES-derived DA neurons generated by current protocols can respond to guidance cues in vitro in a similar manner to fetal cells but also exhibit distinct responses. This may result from developmental differences generated by present in vitro methods of cell patterning or conditioning during ES cell differentiation.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Axons / metabolism*
  • Cell Line
  • Coculture Techniques
  • DCC Receptor
  • Dopamine / metabolism*
  • Embryonic Stem Cells / metabolism*
  • Fetal Stem Cells / metabolism*
  • Fluorescent Antibody Technique
  • Humans
  • Intercellular Signaling Peptides and Proteins / genetics
  • Intercellular Signaling Peptides and Proteins / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Nerve Growth Factors / genetics
  • Nerve Growth Factors / metabolism*
  • Nerve Tissue Proteins / genetics
  • Nerve Tissue Proteins / metabolism*
  • Netrin-1
  • Neurites / metabolism
  • Rats
  • Rats, Sprague-Dawley
  • Receptors, Cell Surface / metabolism
  • Receptors, Immunologic / metabolism
  • Roundabout Proteins
  • Transfection
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism*

Substances

  • DCC Receptor
  • Dcc protein, rat
  • Intercellular Signaling Peptides and Proteins
  • Membrane Proteins
  • NTN1 protein, human
  • Nerve Growth Factors
  • Nerve Tissue Proteins
  • Ntn1 protein, mouse
  • Ntn1 protein, rat
  • Receptors, Cell Surface
  • Receptors, Immunologic
  • SLIT1 protein, human
  • SLIT3 protein, human
  • Tumor Suppressor Proteins
  • Netrin-1
  • Slit homolog 2 protein
  • Dopamine