Y-79 Retinoblastoma Cells: Isolation and Characterization of Clonal Lineages

Y-79 cells are generally undifferentiated, but can be induced to express characteristics of various retinal cell types. Since specific changes occur in only low percentages of cells, it has not been clear whether different agents select different lineages, or if the same cells are differentially responsive. In order to answer this question, we isolated 16 clonal lineages and characterized their responses to various treatment regimes. Dibutyryl cyclic AMP (4 mM) had little effect on cell viability, but treatment with butyrate (1 mM), caused mortality ranging from 20 to 84%. Laminin (100 micrograms ml-1) did not decrease cell growth, and in some cases increased it. The frequency of attachment to a laminin-coated substrate also varied between clones. Comparison of the results for each clone, under all these conditions, indicated that the parental Y-79 line contains at least two different cell types. On the other hand, no obvious differences were found between clones in the morphological changes induced by different agents, evidencing the very plastic nature of Y-79 cells.