mouse monoclonal IgG1; CIITA Antibody (7-1H) is an IgG1 κ mouse monoclonal CIITA antibody (also designated Class II Major Histocompatibility Complex Transactivator antibody, MHC Class II Transactivator antibody, NLR Family Acid Domain Containing antibody, MHC2TA antibody, C2TA antibody, NLRA antibody, Class II Major Histocompatibility Complex Transactivator antibody, or MHC Class II Transactivator antibody) that detects the CIITA protein of mouse, rat and human origin by WB, IP, IF and IHC(P). CIITA Antibody (7-1H) is available as both the non-conjugated anti-CIITA antibody form, as well as multiple conjugated forms of anti-CIITA antibody, including agarose, HRP, PE, FITC and multiple Alexa Fluor® conjugates. The mounting of an immune response and CD4 T cell development in vertebrates require the expression of major histocompatibility complex (MHC) class II molecules. MHC class II molecules are heterodimeric cell surface glycoproteins expressed on B cells, macrophages and dendritic cells, which present antigens to CD4+ T cells. CIITA (class II transactivator) acts as a coactivator for MHC class II-specific gene expression and negatively regulates the IL-4 gene promoter during T cell differentiation. IFNg induces CIITA gene expression via JAK1 and Stat1 pathways. The GTP-binding and acidic, proline-serine-threonine-rich regions appear to be required for CIITA activity. RFX-B (also designated RFXANK and Tvl-1) is the smallest subunit of the RFX complex, which is also required for MHC class II-specific gene transcription. RFX-B contains three ankyrin-repeats that may allow protein-protein interactions between RFX-B and other RFX subunits, and possibly with CIITA and NF-Y. Defects of CIITA and RFX-B have been implicated as causes of Bare Lymphocyte Syndrome (BLS), which is characterized by the absence of MHC class II transcription and severe immunodeficiencies.