Anti-HLA-DR Monoclonal Antibody for WB, IF/ICC, IHC-P, ELISA - P01903

Core Product Specifications and Parameters

Biological Background: HLA-DR Alpha Chain Function and Localization

• HLA-DRA (also known as HLA-DRA1) is a gene on chromosome 6 encoding the alpha chain of MHC class II molecules, with a predicted molecular weight of approximately 29 kDa (mature form around 26 kDa after signal peptide cleavage).
• The encoded alpha chain assembles with beta chain HLA-DRB to form functional HLA-DR heterodimers that present antigenic peptides to CD4-positive T cells, directing T-helper effector functions and macrophage activation (PubMed:15265931, PubMed:15322540, PubMed:17334368). Related references: PMID:15265931 PMID:15322540 PMID:17334368
• Peptide antigen loading follows two distinct processing modes: “bind first, cut/trim later” for pathogen-derived peptides and “cut first, bind later” for self-peptides, with the N-terminal anchor residue (typically a large hydrophobic amino acid) essential for MHCII binding (PubMed:25413013, PubMed:8145819). Related references: PMID:25413013 PMID:8145819
• In the tumor microenvironment, HLA-DR presents tumor-derived antigens captured via phagocytosis or macropinocytosis by APCs, facilitating anti-tumor CD4+ T cell responses (PubMed:31495665). Related references: PMID:31495665
• The HLA-DR complex cycles through endosomal and lysosomal compartments, including autolysosomes where it presents peptides from autophagy-derived intracellular proteins, a mechanism critical for thymic T cell selection and central tolerance (PubMed:17182262, PubMed:23783831). Related references: PMID:17182262 PMID:23783831
• HLA-DRA is expressed at the protein level in professional antigen-presenting cells—macrophages, dendritic cells, B cells—and thymic epithelial cells, consistent with its role in adaptive immunity (PubMed:15322540, PubMed:23783831, PubMed:31495665). Related references: PMID:15322540 PMID:23783831 PMID:31495665
• HLA-DRA is a transmembrane glycoprotein featuring disulfide bonds and potential ubiquitination (isopeptide bond), which may influence its stability and trafficking during immune synapse formation.

Experimental Guidance and Technical Tips

• Immunogen design: The antibody was raised against a peptide within amino acids 100-200 of human HLA-DRA, which is expected to recognize the mature ectodomain; cross-reactivity with other species is not guaranteed but can be tested if needed.
• Western blot (WB): Use reducing conditions and run a molecular weight marker; the detected band should appear at ~29 kDa. Include a positive control lysate from human B-cell lines (e.g., Raji) or PBMCs.
• Immunofluorescence (IF/ICC): Permeabilize cells with 0.1% Triton X-100 to allow antibody access to intracellular epitopes; HLA-DR localizes primarily on the cell surface and endocytic compartments. Use human APCs or HLA-DR-expressing cell lines as positive controls.
• Immunohistochemistry paraffin (IHC-P): Perform heat-induced antigen retrieval in citrate buffer (pH 6.0) before incubation; validate staining on human lymphoid tissues (tonsil, spleen) known to express MHCII.
• ELISA: The antibody can be used in a sandwich ELISA format with a matched detection antibody; validate using recombinant HLA-DR protein or peptide-coated plates.

CamelBio: Your One-Stop Sourcing Bridge

CamelBio offers a streamlined one-stop platform for sourcing IVD raw materials, including this validated anti-HLA-DR monoclonal antibody and complementary reagents such as matched antigen pairs and detection antibodies. Our immunology-focused catalog supports your development of diagnostic assays targeting MHC class II molecules, and our technical teams can assist in customizing reagent formats and scaling supply to meet your project timelines.