MURINE FOREBRAIN AND MIDBRAIN CREST CELLS GENERATE DIFFERENT CHARACTERISTIC DERIVATIVES IN-VITRO

Neural crest (NC) is a transient structure that gives rise to various types of tissues. Many NC cells are pluripotent in the sense that thei r progeny can generate more than one derivative. However, the potentia lity to differentiate into certain derivatives, such as cartilage and bone, seems to be specified with respect to the neuraxial levels at wh ich the NC generates. In order to compare the differentiation potentia lity of different regions of head NC, the derivatives of forebrain and midbrain mouse NC have been investigated in vitro using explant cultu res of neuroepithelial fragments. From morphology and expression of sp ecific markers, the midbrain crest cultures obviously generated earlie r and were greater in number of neuronal cells than were the forebrain ones. Moreover, collagen type II positive cells were detected in the midbrain but not in the forebrain crest cultures. Finally, pigment cel ls were only observed in the forebrain cultures. The result suggest th at the forebrain and midbrain crest cells have a different potentialit y to differentiate.