Adhesion among neural cells of the chick embryo

Cell-cell binding of both retinal and brain cells of the chick embryo varied as a function of developmental age, brain cells acquiring their binding properties at an earlier time than retinal cells. Brain and retinal cells of the appropriate age bound as well to each other as to themselves. Antibodies prepared against a molecule released by retinal cells in culture were able to inhibit cell-cell binding between homologous and heterologous pairs of retinal and brain cells. These results suggest that the molecular mechanism of cell-cell binding is the same in these 2 tissues. Analysis of cell surface proteins precipitated by these antibodies suggest that one of the molecules involved in adhesion has a molecular weight of 150,000, and may be derived from a larger precursor. The possible mechanisms of cell-cell binding are discussed in terms of the properties of this molecule.