Properties of a cell-culture line derived from lymphosarcoma p1798

A cell culture line has been derived from lymphosarcoma P1798. Cultures of this line grow exponentially with a doubling time of about 20-24 h. Cells will not divide in the presence of 10^-8 M dexamethasone. Half-maximal inhibition of proliferation occurs at about 10^-9 M. Half maximal inhibition of [³H] thymidine incorporation occurs at somewhat higher concentrations of dexamethasone. When cells are cultured in the presence of 2 × 10^-7 M dexamethasone they remain 88% viable after 5 days. No decrease in cell number occurs. These cells can be rescued by in vivo passage, and they responded in culture to dexamethasone in exactly the same fashion as do untreated cells. Both dexamethasone rescued and untreated cultured cells contain about 10⁴ dexamethasone receptor sites which bind with a dissociation constant of 4 × 10^-9 M. Cultured cells retain the ability to proliferate both subcutaneously and in ascites. The properties of such tumors resemble those of the parental tumor cell line.