Interleukin-3-associated ganglioside GD1a is induced independently of normal interleukin-3 receptor in murine myelogenous leukaemia NFS60 cells transfected with the interleukin-3 gene

The mechanism of interleukin-3 (IL-3) independent cell growth and of IL-3-associated ganglioside expression was analysed using the IL-3 dependent murine myelogenous leukaemia cell line NFS60-17 andIL-3 gene-transfected sublines. The transfected cell lines showed autonomous cell growth, tumorigenicity, and IL-3 associated ganglioside GD1a expression in spite of their IL-3 production. While the parental NFS60-17 cells did not express significant amounts of GD1a, exogenous recombinant IL-3 (rIL-3) was demonstrated to induce IL-3-associated ganglioside GD1a expression in NFS60-17 cells. Furthermore, the growth potential of the transfected cells was not blocked by anti-IL-3 antibody and expression of GD1a was not affected by anti-IL-3 antibody. These findings suggest that IL-3 expressed intracellularly by gene transfection might act independently of the normal IL-3 receptor on autonomous cell growth and on IL-3-associated GD1a expression in murine myelogenous leukaemia NFS60 cells. Abbreviations: IL-3, interleukin-3; rIL-3, recombinant interleukin-3; FCS, fetal calf serum; PWM-SCCM, pokeweed mitogen-stimulated spleen cell conditioned medium; MTT, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide; DEAE, diethylaminoethyl; HPTLC, high performance thin layer chromatography. Glycosphingolipids are designated according to the recommendation of the Nomenclature Committee of the IUPAC 29] and gangliosides are designated as described 30].