Isolation of a protein responsible for aggregation of avian embryonic cells.

Abstract

CELL adhesion, as a mechanism of morphogenesis in higher organisms, has been explained by two contrasting hypotheses: first, by adhesive macromolecules1, and, second, by a lyophobic colloid mechanism2. Lilien and Moscona3 have reaggregated retina cells with a supernatant preparation taken from a culture of retina cells without, however, investigating the nature of the active compound. Electron microscopy investigations2 have suggested that there are gaps of 100–200 A between the plasmalemmas of living chicken embryonic cells and of many tissues of a variety of species, but were unable to find any intercellular material. We have examined the reaggregation of avian cells to identify the nature of the molecules causing reaggregation if such were found to exist.