Presence and development of ependymal cells in primary tissue cultures derived from embryonic rat cerebral cortex

Using indirect immunohistochemistry, a secondary antibody was detected in a commercial preparation of antiserum against vasoactive intestinal polypeptide. The secondary antibody selectively stained ependymal cells during the first 3 weeks in vitro in cultures of dissociated cerebral cortical tissue from rat. This staining provided a convenient mechanism for investigating the development and properties of these cells in cultures. The overall level of immunofluorescent staining during the initial 3-week time period appeared to directly reflect the proliferation and development of ependymal cells. Fluorescent staining was initially detected in cells which appeared to correspond to matrix cells or progenitor cells from the ependyma. These cells underwent rapid cell division, as evidenced by distinct morphological stages, to yield daughter cells which were the precursors of mature ependymal cells. Three different morphological classes of mature ependymal cells were observed in the cortical cultures. These classes corresponded to the cuboidal, tanycyte and secretory ependymal cell types described in vivo. Direct counting of stained cells showed that these morphological classes were represented in the cultures in roughly the same proportions seen in vivo (cuboidal 75%, tanycyte 19% and secretory 6%). The temporal aspects of ependyma development permitted the staining of developmental stages corresponding to the various morphological classes or types. The morphological sequence of development of the cuboidal cell and tanycyte from the precursor cell or matrix cell--daughter cell was determined. These two cell types displayed marked differences in their developmental sequence. The developmental sequence of the secretory cell could not be resolved; however, what appeared to be multiple morphological subtypes of this cell class were encountered.(ABSTRACT TRUNCATED AT 250 WORDS)