• Product nameAnti-HLA DR antibody [MEM-267]
    See all HLA DR primary antibodies
  • Description
    Mouse monoclonal [MEM-267] to HLA DR
  • SpecificityThis antibody specifically binds to the empty but not peptide loaded form of HLA DR1.
  • Tested applicationsSuitable for: WB, Flow Cyt, ELISA, IHC-Pmore details
  • Species reactivity
    Reacts with: Human
  • Immunogen

    Purified, insoluble Human DR1 beta chain (DRB1*0101) expressed in E. coli inclusion bodies.

  • Positive control
    • This antibody gave a positive result in IHC in the following FFPE tissue: Human Hodgekins lymphoma.


  • FormLiquid
  • Storage instructionsShipped at 4°C. Store at +4°C short term (1-2 weeks). Upon delivery aliquot. Store at -20°C long term.
  • Storage bufferPreservative: 15mM Sodium Azide.
    Constituents: PBS, pH 7.4.
  • Concentration information loading...
  • PurityProtein A purified
  • Purification notesThis antibody was purified from ascites by affinity chromatography. > 95% (by SDS-PAGE).
  • ClonalityMonoclonal
  • Clone numberMEM-267
  • IsotypeIgG2b
  • Research areas


Our Abpromise guarantee covers the use of ab26089 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
Flow Cyt
  • Application notesELISA: Use at an assay dependent dilution.
    Flow Cyt: Use at an assay dependent dilution. The antibody stains immature dendritic cells that express empty cell surface MHC molecules, but not cells that express predominantly peptide loaded forms.
    WB: Use at an assay dependent dilution. Predicted molecular weight: 26-28 kDa.

    Not yet tested in other applications.
    Optimal dilutions/concentrations should be determined by the end user.
  • Target

    • FunctionBinds peptides derived from antigens that access the endocytic route of antigen presenting cells (APC) and presents them on the cell surface for recognition by the CD4 T-cells. The peptide binding cleft accommodates peptides of 10-30 residues. The peptides presented by MHC class II molecules are generated mostly by degradation of proteins that access the endocytic route, where they are processed by lysosomal proteases and other hydrolases. Exogenous antigens that have been endocytosed by the APC are thus readily available for presentation via MHC II molecules, and for this reason this antigen presentation pathway is usually referred to as exogenous. As membrane proteins on their way to degradation in lysosomes as part of their normal turn-over are also contained in the endosomal/lysosomal compartments, exogenous antigens must compete with those derived from endogenous components. Autophagy is also a source of endogenous peptides, autophagosomes constitutively fuse with MHC class II loading compartments. In addition to APCs, other cells of the gastrointestinal tract, such as epithelial cells, express MHC class II molecules and CD74 and act as APCs, which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen, three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form an heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs, CD74 undergoes a sequential degradation by various proteases, including CTSS and CTSL, leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells, the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal miroenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading.
    • Sequence similaritiesBelongs to the MHC class II family.
      Contains 1 Ig-like C1-type (immunoglobulin-like) domain.
    • Post-translational
      Ubiquitinated by MARCH1 or MARCH8 at Lys-244 leading to down-regulation of MHC class II. When associated with ubiquitination of the beta subunit of HLA-DR: HLA-DRB4 'Lys-254', the down-regulation of MHC class II may be highly effective.
    • Cellular localizationCell membrane. Endoplasmic reticulum membrane. Golgi apparatus > trans-Golgi network membrane. Endosome membrane. Lysosome membrane. Late endosome membrane. The MHC class II complex transits through a number of intracellular compartments in the endocytic pathway until it reaches the cell membrane for antigen presentation.
    • Information by UniProt
    • Database links
    • Alternative names
      • DR alpha chain antibody
      • DR alpha chain precursor antibody
      • DRA_HUMAN antibody
      • DRB1 antibody
      • DRB4 antibody
      • Histocompatibility antigen HLA DR alpha antibody
      • HLA class II histocompatibility antigen antibody
      • HLA class II histocompatibility antigen DR alpha chain antibody
      • HLA DR1B antibody
      • HLA DR3B antibody
      • HLA DRA antibody
      • HLA DRA1 antibody
      • HLA DRB1 antibody
      • HLA DRB3 antibody
      • HLA DRB4 antibody
      • HLA DRB5 antibody
      • HLA-DRA antibody
      • HLADR4B antibody
      • HLADRA1 antibody
      • HLADRB antibody
      • Major histocompatibility complex class II DR alpha antibody
      • Major histocompatibility complex class II DR beta 1 antibody
      • Major histocompatibility complex class II DR beta 3 antibody
      • Major histocompatibility complex class II DR beta 4 antibody
      • Major histocompatibility complex class II DR beta 5 antibody
      • MGC117330 antibody
      • MHC cell surface glycoprotein antibody
      • MHC class II antigen DRA antibody
      • MHC II antibody
      • MLRW antibody
      see all

    Anti-HLA DR antibody [MEM-267] images

    • IHC image of HLA DR staining in Human Hodgekins lymphoma formalin fixed paraffin embedded tissue section, performed on a Leica Bond™ system using the standard protocol F. The section was pre-treated using heat mediated antigen retrieval with sodium citrate buffer (pH6, epitope retrieval solution 1) for 20 mins. The section was then incubated with ab26089, 5µg/ml, for 15 mins at room temperature and detected using an HRP conjugated compact polymer system. DAB was used as the chromogen. The section was then counterstained with haematoxylin and mounted with DPX.


      For other IHC staining systems (automated and non-automated) customers should optimize variable parameters such as antigen retrieval conditions, primary antibody concentration and antibody incubation times.

    • All lanes : Anti-HLA DR antibody [MEM-267] (ab26089)

      Lane 1 : Cell lysate prepared from human Raji cells
      Lane 2 : Cell lysate prepared from Jurkat cells

      Predicted band size : 26-28 kDa

    References for Anti-HLA DR antibody [MEM-267] (ab26089)

    This product has been referenced in:
    • Carven GJ  et al. Monoclonal antibodies specific for the empty conformation of HLA-DR1 reveal aspects of the conformational change associated with peptide binding. J Biol Chem 279:16561-70 (2004). Read more (PubMed: 14757758) »
    • Carven GJ  et al. Monoclonal antibodies specific for the empty conformation of HLA-DR1 reveal aspects of the conformational change associated with peptide binding. J Biol Chem 279:16561-70 (2004). WB, ELISA, Flow Cyt, Sandwich ELISA ; Human . Read more (PubMed: 14757758) »

    See all 2 Publications for this product

    Product Wall

    There are currently no Abreviews or Questions for ab26089.
    Please use the links above to contact us or submit feedback about this product.