Fig. 8.

NCSC-derived myofibroblasts express the endoneurial fibroblast marker Thy1, and the generation of these cells is enhanced by Bmp4, Nrg1 and Delta. (A,D) After 14 days in standard medium, nerve NCSCs give rise to myofibroblasts that are either SMA⁺Thy1⁻ (purple arrows; 46±17% of cells with myofibroblast morphology), SMA⁺Thy1⁺ (white arrows; 44±15%), or SMA⁻Thy1⁺ (white arrowhead; 10±3%). Note that these colonies also contain large numbers of neurons and glia that are not visible in this field of view. After only 6 days in standard medium (B,D), NCSCs give rise to colonies containing mainly undifferentiated cells, as well as small numbers of myofibroblasts, which are mostly (92±6%) SMA⁺Thy1⁻ (purple arrows). (C,D) In 6 day cultures supplemented with Delta, Nrg1 and Bmp4, nerve NCSCs give rise to larger numbers of myofibroblast cells, that include a higher frequency of SMA⁺Thy1⁺ cells (white arrows; 60±8%), and SMA⁻Thy1⁺ cells (white arrowhead; 28±7%) and a lower frequency of SMA⁺Thy1⁻ cells (not shown; 12±4%). *P<0.05, relative to 6 day No Add (standard medium without Delta, Nrg1 or Bmp4 added);∂ indicates P<0.05, relative to 14 day No add (D). (E) Neural crest-derived myofibroblast progenitors can be isolated from acutely dissociated fetal rat sciatic nerve as p75⁻P₀ ⁺ cells. (F) On average, 40±11% of these p75⁻P₀ ⁺ cells express Thy1 in vivo. (G) 100% of the colonies that arose in culture from these p75⁻P₀⁺Thy1⁺ cells were myofibroblast-only, and about 83% of these colonies consisted exclusively of SMA⁺Thy1⁻ cells.