Sialic acid in prednisolone treated HeLa cells; suggested mechanism for elevated levels at the cell surface

The accumulation of sialic acid at the periphery of Hela cells grown in the presence of prednisolone was demonstrated to be the result of a decreased shedding of sialopeptides by the treated cells. Two such sialopeptide fractions were isolated from the spent medium in which HeLa cells had been grown. Such compounds could be responsible for the apparent increase in cell density-induced growth inhibition which can be demonstrated in heteroploid cells grown in media that contain low concentrations of glucocorticoids.