Down-regulation of interferon-gamma-induced class II expression on human glioma cells by recombinant interferon-beta: effects of dosage treatment schedule.
We have examined the influence of human recombinant interferon-beta (IFN-beta) and interferon-gamma (IFN-gamma) on class II antigen expression on cultured glioblastoma multiforme cells by flow cytometry. Class II molecules were not constitutively expressed on these cells, nor induced by IFN-beta. IFN-gamma increased class II expression in a dose-dependent fashion. We demonstrate that IFN-beta is either antagonistic or synergistic with IFN-gamma in class II induction depending upon dose and schedule of administration. Both interferons at 100 IU/ml reduce class II expression by 18%, compared to IFN-gamma alone. Pretreatment with IFN-beta for 72 h, followed by both interferons yielded a 90% reduction. In contrast, lower concentrations (10 IU/ml) of both interferons were synergistic.
Joseph
J
J
Department of Neurology, Thomas Jefferson University, Philadelphia, PA 19107.
Knobler
R L
RL
D'Imperio
C
C
Lublin
F D
FD
D004334:Drug Administration Schedule; D004338:Drug Combinations; D004357:Drug Synergism; D005434:Flow Cytometry; D005909:Glioblastoma / Q000276:immunology* / Q000473:pathology; D006684:HLA-DR Antigens / Q000032:analysis*; D006801:Humans; D007370:Interferon Type I / Q000494:pharmacology*; D007371:Interferon-gamma / Q000494:pharmacology*; D011994:Recombinant Proteins; D014407:Tumor Cells, Cultured
D004338:Drug Combinations; D006684:HLA-DR Antigens; D007370:Interferon Type I; D011994:Recombinant Proteins; D007371:Interferon-gamma