Lanthanum Staining of Developing Chick Cartilage and Reaggregating Cartilage Cells

In this report intercellular material in developing cartilage and between reaggregating cartilage cells has been examined with lanthanum staining (3, 7, 13, 16) . The proteinpolysaccharides of cartilage have been extensively studied by biochemical methods (2, 8-10, 18-21), and proteinpolysaccharide extracted from cartilage has been shown to precipitate with lanthanum (2) . The lanthanum-staining properties of normal developing cartilage were compared with those of tissue which had been treated enzymatically . In addition, lanthanum staining of early and late reaggregates was compared. These studies showed that (a) lanthanum staining is characteristically associated with what are believed to be proteinpolysaccharide components of the developing matrix, (b) the matrix as revealed by lanthanum is formed early in reaggregation, and (c) there is a change in the morphology of the matrix as aggregates mature .