title: Enhancement of colony-stimulating activity (CSA) on murine CFU-gm by the H-4-II-E2 (H4) tumor cell line of the rat.
abstract: The effect of the H-4-II-E2 (H4) rat tumor cell line on murine granulocyte/macrophage colony-forming units (CFU-gm) was studied in vitro using a bilayer (agar/methylcellulose) culture system over the tumor cell feeder and 10% colony-stimulating activity (CSA). The H4 cells demonstrated an amplification of CSA from several sources and of CFU-gm growth of murine marrow, including the CSA present in L-cell-conditioned medium (L-CSA; 200% of control). The amplification did not result from CSA produced by the H4 cell line, nor was cell-to-cell contact necessary for enhanced CFU-gm growth. Amplification of L-CSA was not mediated by endogenous or exogenous prostaglandin E concentrations in the in vitro system. Furthermore, incubation of the non-adherent marrow cell population with H4 tumor cells for 24 h prior to assaying for CFU-gm resulted in more colonies, independent of the continued presence of H4 tumor cells. The data suggest that the H4 tumor cells produce a readily diffusable, soluble factor that may amplify the effect of L-CSA on CFU-gm by stimulating a more primitive progenitor cell that expands the CFU-gm population.
mesh_terms: D000818:Animals; D002448:Cell Adhesion; D002460:Cell Line; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000502:physiology; D015232:Dinoprostone; D006098:Granulocytes / Q000502:physiology*; D006410:Hematopoiesis / Q000187:drug effects; D007213:Indomethacin / Q000494:pharmacology; D008114:Liver Neoplasms, Experimental / Q000503:physiopathology*; D008264:Macrophages / Q000502:physiology*; D008297:Male; D051379:Mice; D011458:Prostaglandins E / Q000494:pharmacology
chemical_list: D003115:Colony-Stimulating Factors; D011458:Prostaglandins E; D015232:Dinoprostone; D007213:Indomethacin