Regulation of Class II MHC Expression in APCs: Roles of Types I, III, and IV Class II Transactivator

Regulation of class II MHC expression in APCs: roles of types I, III, and IV class II transactivator.

Class II transactivator (CIITA) is necessary for expression of class II MHC (MHC-II) molecules. In mice, CIITA expression is regulated by three promoters (pI, pIII, and pIV), producing types I, III, and IV CIITA. The relative roles of different CIITA types remain unclear. Unstimulated bone marrow-derived macrophages expressed low levels of CIITA mRNA; type I CIITA was nine times more abundant t...

Deregulated MHC Class II Transactivator

Class II Transactivator Modulation of Gene Expression by the MHC

Activated human T cells accomplish MHC class II expression through T cell-specific occupation of class II transactivator promoter III.

Activated human T cells express HLA-DR, HLA-DQ, and HLA-DP on their surface, but the regulation and functioning of MHC class II molecules in T lymphocytes are poorly understood. Because the MHC class II transactivator (CIITA) is essential for MHC class II expression, we have investigated transcriptional activation of CIITA in activated T cells. In this study, we show that in human activated CD4...

PML promotes MHC class II gene expression by stabilizing the class II transactivator

Promyelocytic leukemia (PML) nuclear bodies selectively associate with transcriptionally active genomic regions, including the gene-rich major histocompatibility (MHC) locus. In this paper, we have explored potential links between PML and interferon (IFN)-γ-induced MHC class II expression. IFN-γ induced a substantial increase in the spatial proximity between PML bodies and the MHC class II gene...