{"product_id":"recombinant-human-hla-class-ii-histocompatibility-antigen-dr-alpha-chain-hla-dra-bhp10505096","title":"Recombinant Human HLA class II histocompatibility antigen, DR alpha chain (HLA-DRA)","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\u003cp\u003eRecombinant Human HLA class II histocompatibility antigen, DR alpha chain (HLA-DRA) is a recombinant protein reagent for research-use applications such as assay development, binding studies, and mechanistic experiments. It corresponds to \u003cstrong\u003eHLA-DRA\u003c\/strong\u003e (Homo sapiens (Human)) and is intended for RUO workflows where a defined protein standard or functional input is needed.\u003c\/p\u003e\u003ch2\u003eKey elements and design rationale\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpression system:\u003c\/strong\u003e Yeast (expression context can influence folding and PTMs).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpression region:\u003c\/strong\u003e 26-254aa (region choice can affect activity and binding readouts).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eConjugate(s)\/tag:\u003c\/strong\u003e N-terminal 6xHis-tagged (can support detection or purification depending on format).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMolecular weight:\u003c\/strong\u003e 28 kDa (useful for interpreting gel migration and size-exclusion profiles).\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eWhen comparing results across assays, consider that expression system and expressed region can alter glycosylation, disulfide formation, and oligomerization state, which may shift apparent potency or binding behavior in vitro.\u003c\/p\u003e\u003ch2\u003eBiological background\u003c\/h2\u003e\u003cp\u003eBinds 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 a 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 microenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading.\u003c\/p\u003e\u003ch2\u003eResearch relevance and current trends\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eReagent standardization: using recombinant proteins as reference materials for quantitative calibration and cross-study comparability.\u003c\/li\u003e\n\u003cli\u003eInteraction-focused studies: mapping binding partners, affinity changes, and structure–function relationships across variants or domains.\u003c\/li\u003e\n\u003cli\u003eMulti-omic readouts: combining recombinant perturbations with transcript, protein, and functional endpoints to connect mechanism to phenotype.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCommon research applications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eAssay development and validation: use as a defined input or standard where protein identity is required.\u003c\/li\u003e\n\u003cli\u003eBinding studies: evaluate interaction strength and specificity using plate-based or biophysical formats.\u003c\/li\u003e\n\u003cli\u003eCell-response profiling: add protein to cultured cells and interpret downstream marker changes with appropriate controls.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eInterpretation is most robust when signal changes are evaluated relative to matched controls (buffer-only, unrelated protein controls, or pathway controls) and when readouts are compared across dose and time.\u003c\/p\u003e\u003ch2\u003eNotes for experimental interpretation\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eIsoforms and PTMs can influence binding and activity; ensure the expressed region and expression system match your experimental needs.\u003c\/li\u003e\n\u003cli\u003eSpecies differences may affect receptor binding or antibody recognition; confirm species\/source alignment with your model.\u003c\/li\u003e\n\u003cli\u003eUse concept-level controls such as negative controls (no protein), matrix controls, or orthogonal readouts to support conclusions.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c!-- Sources (internal): - UniProt keyword search: https:\/\/www.uniprot.org\/uniprotkb?query=HLA-DRA - NCBI Gene search: https:\/\/www.ncbi.nlm.nih.gov\/gene\/?term=HLA-DRA - PubMed search: https:\/\/pubmed.ncbi.nlm.nih.gov\/?term=HLA-DRA - Ensembl search: https:\/\/www.ensembl.org\/Multi\/Search\/Results?q=HLA-DRA - Reactome Pathway Browser: https:\/\/reactome.org\/content\/query?q=HLA-DRA --\u003e","brand":"CUSABIO TECHNOLOGY LLC","offers":[{"title":"1 mg","offer_id":53053077455213,"sku":"CSB-YP360793HU-1MG","price":2010.0,"currency_code":"USD","in_stock":true},{"title":"100 ug","offer_id":53053254500717,"sku":"CSB-YP360793HU-100UG","price":470.0,"currency_code":"USD","in_stock":true},{"title":"20 ug","offer_id":53053254533485,"sku":"CSB-YP360793HU-20UG","price":250.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7424\/7277\/files\/CSB-YP360793HU-SDS.jpg?v=1772173001","url":"https:\/\/www.ebiohippo.com\/products\/recombinant-human-hla-class-ii-histocompatibility-antigen-dr-alpha-chain-hla-dra-bhp10505096","provider":"BioHippo","version":"1.0","type":"link"}