Transforming growth factor-beta 2 down-regulates HLA-DR antigen expression on human malignant glioma cells.
Transforming growth factor-beta (TGF-beta) is known to have a potent inhibitory influence on several immune functions. It has recently been demonstrated that TGF-beta 2 is identical to the glioblastoma-derived T cell suppressor factor (G-TsF). In the present study, human malignant glioma cell lines were incubated with various concentrations of TGF-beta 2. An optimal concentration of 1 ng/ml TGF-beta 2 produced a partial but significant decrease of HLA-DR (class II) surface antigen expression on glioma cells expressing this antigen, as well as decreased levels of HLA-DR-specific mRNA. The surface expression of other HLA-related molecules, such as HLA-ABC (class I) and beta 2-microglobulin, was not influenced by TGF-beta 2. The suppressive effect of TGF-beta 2 on HLA-DR expression, both at the surface antigenic and cytoplasmic mRNA levels, could be completely overcome by adding relatively high concentrations (500 U/ml) of interferon (IFN)-gamma to the culture system. However, TGF-beta 2 inhibited the enhancement of HLA-DR surface expression produced by low concentrations of IFN-gamma on some cells which initially did not express these antigens. These results show that TGF-beta 2 can act as a regulator of HLA-DR antigen expression on human glioma cells.
D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology*; D015152:Blotting, Northern; D005434:Flow Cytometry; D005910:Glioma / Q000276:immunology*; D006680:HLA Antigens / Q000276:immunology; D006684:HLA-DR Antigens / Q000235:genetics / Q000276:immunology*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics; D011994:Recombinant Proteins; D015291:Transforming Growth Factors / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D001613:beta 2-Microglobulin / Q000276:immunology
D000951:Antigens, Neoplasm; D006680:HLA Antigens; D006684:HLA-DR Antigens; D012333:RNA, Messenger; D011994:Recombinant Proteins; D001613:beta 2-Microglobulin; D015291:Transforming Growth Factors; D007371:Interferon-gamma