Different susceptibilities of cultured mouse cell lines to mouse interferon.
Cultured mouse cells were treated with 3.3 approximately 10,000 units of mouse interferononon for 3 days and further cultivated in fresh medium for 2 days (recovery incubation). The IC50 (concentration of drug required for 50% inhibition) of interferon was not changed much after the recovery incubation. The most susceptible cell line to interferon was B16 melanoma; the IC50 was 10.5 units per ml of medium on day 3 after the start of treatment. P388 leukemic cells, Lewis lung carcinoma cells, and colon adenocarcinoma 38 cells were moderately susceptible to interferon and the IC50s of these cell lines were 200, 80, and 180 units per ml medium, respectively, on day 3. The cells least susceptible to interferon were those of colon adenocarcinoma 26; IC50 was greater than 10,000 units per ml. In the recovery incubation, the growth of B16 melanoma cells, P388 leukemic cells, Lewis lung carcinoma cells and colon adenocarcinoma 38 cells was considerably inhibited when these cells were treated with more than 100 approximately, 1,000 units of interferon per ml medium. The rate of multiplication was usually more than 1 for these cell lines, except for Lewis lung carcinoma cells where the rate of multiplication was less than 1. This indicates that interferon is not cytocidal towards B16 melanoma cells, P388 leukemic cells, or colon adenocarcinoma 38 cells, but mouse interfer is cytocidal towards Lewis lung carcinoma cells when the cells are treated with a relatively high concentration of interferon and then cultured in the medium without interferon.
D000230:Adenocarcinoma / Q000628:therapy; D000818:Animals; D002455:Cell Division; D002460:Cell Line; D007372:Interferons / Q000627:therapeutic use*; D007941:Leukemia P388 / Q000628:therapy; D008175:Lung Neoplasms / Q000628:therapy; D008545:Melanoma / Q000628:therapy; D051379:Mice; D009374:Neoplasms, Experimental / Q000628:therapy*
D007372:Interferons