Fig. 4

In vitro effects of NA and complement on the ependymal epithelium. Explants from the septal side of the lateral ventricle wall were placed in culture and treated with NA and/or complement for 2 h. Rat serum was used as a source of complement. The ependyma in the explants was then evaluated by histology. Anti-vimentin allowed the location of the ependyma in the explants (a, d, g, j). The squared regions are those magnified in the hematoxylin-eosin staining (b, e, h, k). The sialic acid removal by NA was confirmed by binding of the lectin PNA (peanut agglutinin; c, f, i, l). Ependymal damage occurred in explants treated with NA (e, k) and was worsened by the presence of serum (k). The concurrence of NA and serum resulted in the loss of epithelium integrity, where gaps could be seen (arrowheads in l). Serum alone did not produce such damage (e). CM culture medium, NA neuraminidase, Ep ependyma, NP nervous parenchyma. (Arrows) Damaged ependymal cells