Class II transactivator (CIITA) is a global transcriptional coactivator of human leukocyte antigen-D (HLA-D) genes. CIITA contains motifs similar to guanosine triphosphate (GTP)-binding proteins. This report shows that CIITA binds GTP, and mutations in these motifs decrease its GTP-binding and transactivation activity. Substitution of these motifs with analogous sequences from Ras restores CIIT...

The aim of the present study was to explore the effect of epigenetic modification of class II transactivator (CIITA) methylation on histocompatibility complex (MHC) class II expression and the immune evasion of leukemia HL-60 cells. HL-60 cells were treated with various concentrations of 5-aza-2'deoxycytidine (5-Aza-CdR) and 0.5 µmol/l suberoylanilide hydroxamic acid (SAHA) for 24 h and then st...

Astrocytes are nonprofessional APCs that may participate in Ag presentation and activation of pathogenic CD4+ T cells involved in central nervous system (CNS) inflammatory diseases. Using immortalized pure astrocytes as a complement to the study of primary astrocytes, we investigated whether these astrocytes express elements involved in the class II endocytic pathway and if they are capable of ...

Chronic inflammation impairs metabolic homeostasis and is intimately correlated with the pathogenesis of type 2 diabetes. The pro-inflammatory cytokine IFN-γ is an integral part of the metabolic inflammation circuit and contributes significantly to metabolic dysfunction. The underlying mechanism, however, remains largely unknown. In the present study, we report that IFN-γ disrupts the expressio...

PURPOSE We have shown previously that the MHC class II-negative murine TS/A adenocarcinoma is rejected in vivo if induced to express MHC class II molecules by transfection of the MHC class II transactivator CIITA. In this study, we explored the immunologic basis of tumor rejection and the correlation between histopathology of tumor tissue and immune rejection. EXPERIMENTAL DESIGN Stable TS/A-...

UNLABELLED Major histocompatibility complex class II (MHC-II) molecules play a central role in adaptive antiviral immunity by presenting viral peptides to CD4(+) T cells. Due to their key role in adaptive immunity, many viruses, including Kaposi's sarcoma-associated herpesvirus (KSHV), have evolved multiple strategies to inhibit the MHC-II antigen presentation pathway. The expression of MHC-II,...

We report that chlamydiae, which are obligate intracellular bacterial pathogens, can inhibit interferon (IFN)-gamma-inducible major histocompatibility complex (MHC) class II expression. However, the IFN-gamma-induced IFN regulatory factor-1 (IRF-1) and intercellular adhesion molecule 1 (ICAM-1) expression is not affected, suggesting that chlamydia may selectively target the IFN-gamma signaling ...

The transcription factor TFIID components TAF7 and TAF1 regulate eukaryotic transcription initiation. TAF7 regulates transcription initiation of TAF1-dependent genes by binding to the acetyltransferase (AT) domain of TAF1 and inhibiting the enzymatic activity that is essential for transcription. TAF7 is released from the TAF1-TFIID complex upon completion of preinitiation complex assembly, allo...

BACKGROUND The Pr55(gag) (Gag) polyprotein of HIV serves as a scaffold for virion assembly and is thus essential for progeny virion budding and maturation. Gag localizes to the plasma membrane (PM) and membranes of late endosomes, allowing for release of infectious virus directly from the cell membrane and/or upon exocytosis. The host factors involved in Gag trafficking to these sites are large...

The MHC class II transactivator gene (CIITA) is an important transcription factor regulating gene required for HLA class II MHC-restricted antigen presentation. Association with HLA class II variation, particularly HLA-DRB1*1501, has been well-established for multiple sclerosis (MS). In addition, the -168A/G CIITA promoter variant (rs3087456) has been reported to be associated with MS. Thus, a ...