Some effects of trypsin dissociation on the inhibition of reaggregation among embryonic chicken neural retina cells by cycloheximide

The effects of cycloheximide on the reaggregation of trypsin-dispersed, embryonic chicken, neural retina cells were investigated. The cells were used either immediately after isolation (F-cells), or after 24 hr prior culture under conditions not permitting reaggregation (V-cells). The parameters of aggregation used were the size of aggregates formed in gyrotatory shaker cultures, and the concentration of single cells in these cultures. At both 24 and 48 hr, following treatment with cycloheximide, the mean diameters of the aggregates of F-cells showed a greater reduction than the V-cells, when compared with their corresponding controls. In addition, cycloheximide resulted in a higher concentration of single cells, that is less cell/cell adhesion, than in comparable controls. A higher proportion of single cells were present in the F-cell cultures in the presence of cycloheximide than in the V-cell cultures. Thus, the degree of inhibition of cell adhesion by one inhibitor of protein synthesis differed in F-cells and V-cells. These experiments may serve to focus attention on some secondary effects of tryptic dissociation, which is an often overlooked factor in subsequent studies of reaggregating embryonic cells, particularly in those experiments involving the use of metabolic inhibitors.