Attachment of neural crest cells to endogenous extracellular matrices.

Newly emerging neural crest (NC) cells will enter either the lateral pathway under the surface ectoderm or the vental pathway along the neural tube depending on the axial level (Pratt et al.: Dev. Biol., 44:298-305, 1975; Thiery et al.: Dev. Biol., 93:324-343, 1982; Newgreen et al.: Cell Tissue Res., 221:521-549, 1982; LeDouarin et al.: In: The Role of Extracellular Matrix in Development. Alan R. Liss, Inc., New York, pp. 373-398, 1984; Brauer et al.: Anat. Rec., 211:57-68, 1985). A number of studies have shown a correlation between the type of extracellular matrix (ECM) associated with adjacent tissues (e.g., ectoderm, neural tube, and mesoderm) and the initial pathway taken by NC cells. Our working hypothesis is that the direction of NC cell migration (ventral vs. lateral pathway) depends on the composition of the ECM associated with the surface ectoderm and its ability to support NC cell attachment. In this study, we tested this hypothesis by isolating endogenous ECM associated with the ectoderm of each region and examining the ability of each endogenous ECM to support cranial and trunk NC cell attachment in vitro. Results indicated that both cranial and trunk NC cells preferentially attached to cranial ectodermal ECM as compared to trunk ectodermal ECM. The differences in NC cell attachment were not due to a preferential adsorption of cranial ectodermal ECM onto the ECM-conditioned plastic substrate over trunk ectodermal since approximately equal amounts of ECM bound to the plastic. These results supported the hypothesis and provide evidence that endogenous ectodermal ECM may be one factor potentially responsible for directing the NC cells along a ventral or a lateral pathway.