AN ANALYSIS OF DIFFERENTIATIVE CAPACITY OF PIGMENTED EPITHELIAL CELLS OF ADULT NEWT IRIS IN CLONAL CELL CULTURE

Abstract

Singly dissociated cells from dorsal and ventral iris epithelia (iris iridica) of adult newts [Triturus pyrrhogaster] were cultured separately at clonal density to analyze their growth and differentiative capacity. Usually some attached cells began to proliferate on the 12th day of culture, and grew with loss of melanosomes to form clonal cell colonies. Up to 30 days after inoculation most of the clonal colonies formed typical epithelial monolayer sheets which consisted mostly of nonpigmented cells. Then, in some of those colonies, cells piled up together and formed typical lens structures containing lens antigens. At 1.5 mo. after culturing, 30-40% of single iris cells, which was previously marked, grew to form clonal colonies consisting of more than 100 cells. About 30% of these colonies expressed lens specificity, and no significant differences in efficiency of colony formation and differentiation were detected between the dorsal cells and the ventral, suggesting that potent cells capable of transdifferentiating into lens cells are evenly distributed in all parts of the newt iris epithelium.