Induction of assembly of MHC class I heavy chains with beta 2microglobulin by interferon-gamma
Klar, D.; Hämmerling, G.J.
EMBO Journal 8(2): 475-481
1989
ISSN/ISBN: 0261-4189 PMID: 2498080 Document Number: 340766
Assembly of histocompatibility class I heavy chains with beta 2microglobulin (beta 2m) is known to be necessary for cell surface expression. Studies on the H-2 class I deficient but interferon-gamma (IFN-gamma) inducible fibrosarcoma BC2 and the lung carcinoma CMT 64.5 showed that after transfection with allogeneic H-2 class I genes the class I proteins are expressed, but only intracellularly and not on the cell surface. In spite of the presence of beta 2m in the cells no association of the transfected class I chain with beta 2m was observed. However, stimulation with IFN-gamma induced assembly and subsequent surface expression. These findings show that the assembly of class I heavy chains with beta 2m is not a spontaneous event but appears to be regulated by cellular mechanisms the nature of which is still unknown.