The inhibition of cell aggregation by a pure serum protein

Abstract

The aggregation of isolated cells into coherent multicellular bodies is widely thought to be due mainly if not entirely to the adhesiveness of the cells for one another, according to Moscona (1961a, b), Curtis (1962) and Steinberg (1962a) amongst others. In consequence the aggregation of cells from dispersed (disaggregated) tissues has been widely used as a test for the degree of adhesiveness shown by the cells, and conditions affecting aggregation have been interpreted as affecting cell adhesion. Using this type of test Moscona (1961a, b) found that embryonic chick cells would not aggregate at temperatures below 14° C. It was also discovered that aggregation was inhibited at 37° C. by puromycin and actinomycin D (Moscona & Moscona, 1963), by glucosamine-HCl (Garber, 1963), and by chloramphenicol (Nakanishi et al., 1963). Moscona concluded from the failure of aggregation at low temperatures that the metabolic synthesis of an adhesive substance was being prevented under such conditions and this interpretation was reinforced by the evidence of chemical inhibition of aggregation. Moscona (1962) suggested that the adhesive substance was responsible for producing cell to cell adhesion. In all these experiments cells were aggregated in media containing serum, usually horse serum.