ELISA/assay

Human HLA class II histocompatibility antigen, DR alpha chain, HLA-DRA ELISA Kit

MBS706908

48-Strip-Wells

510 USD

ELISA Kit

Human HLA class II histocompatibility antigen, DR alpha chain, HLA-DRA ELISA Kit

HLA class II histocompatibility antigen, DR alpha chain

Human HLA class II histocompatibility antigen; DR alpha chain (HLA-DRA) ELISA kit; DASS-397D15.1; HLA-DRA1; HLA class II histocompatibility antigen; DR alpha chain; MHC cell surface glycoprotein; histocompatibility antigen HLA-DR alpha major histocompatibility complex; class II; DR alpha (HLA-DRA) ; HLA class II histocompatibility antigen; DR alpha chain

HLA class II histocompatibility antigen, DR alpha chain; HLA class II histocompatibility antigen, DR alpha chain; HLA class II histocompatibility antigen, DR alpha chain; MHC class II antigen DRA; MHC cell surface glycoprotein; histocompatibility antigen HLA-DR alpha; major histocompatibility complex, class II, DR alpha; MHC class II antigen DRA

HLA-DRA

HLA-DRA; HLA-DRA; MLRW; HLA-DRA1; HLA-DRA1

DRA_HUMAN

Human

254

This assay has high sensitivity and excellent specificity for detection of human HLA-DRA. No significant cross-reactivity or interference between human HLA-DRA and analogues was observed.

Unopened test kits should be stored at 2 to 8 degree C upon receipt. Please refer to pdf manual for further storage instructions.

Samples: Serum, plasma, tissue homogenates. Assay Type: Sandwich. Detection Range: 18.75 pg/ml -1200 pg/ml. Sensitivity: The minimum detectable dose of human HLA-DRA is typically less than 4.68 pg/ml. The sensitivity of this assay, or Lower Limit of Detection (LLD) was defined as the lowest protein concentration that could be differentiated from zero. It was determined the mean O.D value of 20 replicates of the zero standard added by their three standard deviations.

Intra-assay Precision: Intra-assay Precision (Precision within an assay): CV%<8%. Three samples of known concentration were tested twenty times on one plate to assess. Inter-assay Precision: Inter-assay Precision (Precision between assays): CV%<10%. Three samples of known concentration were tested in twenty assays to assess.

Principle of the assay: This assay employs the quantitative sandwich enzyme immunoassay technique. Antibody specific for HLA-DRA has been pre-coated onto a microplate. Standards and samples are pipetted into the wells and any HLA-DRA present is bound by the immobilized antibody. After removing any unbound substances, a biotin-conjugated antibody specific for HLA-DRA is added to the wells. After washing, avidin conjugated Horseradish Peroxidase (HRP) is added to the wells. Following a wash to remove any unbound avidin-enzyme reagent, a substrate solution is added to the wells and color develops in proportion to the amount of HLA-DRA bound in the initial step. The color development is stopped and the intensity of the color is measured.

52426774

NP_061984.2

NM_019111.4

P01903

28,607 Da

Adaptive Immune System Pathway (366160); Allograft Rejection Pathway (920963); Allograft Rejection Pathway (83123); Allograft Rejection Pathway (535); Antigen Processing And Presentation Pathway (83074); Antigen Processing And Presentation Pathway (485); Asthma Pathway (83120); Asthma Pathway (532); Autoimmune Thyroid Disease Pathway (83121); Autoimmune Thyroid Disease Pathway (533)

HLA-DRA is one of the HLA class II alpha chain paralogues. This class II molecule is a heterodimer consisting of an alpha and a beta chain, both anchored in the membrane. It plays a central role in the immune system by presenting peptides derived from extracellular proteins. Class II molecules are expressed in antigen presenting cells (APC: B lymphocytes, dendritic cells, macrophages). The alpha chain is approximately 33-35 kDa and its gene contains 5 exons. Exon 1 encodes the leader peptide, exons 2 and 3 encode the two extracellular domains, and exon 4 encodes the transmembrane domain and the cytoplasmic tail. DRA does not have polymorphisms in the peptide binding part and acts as the sole alpha chain for DRB1, DRB3, DRB4 and DRB5. [provided by RefSeq, Jul 2008]

Function: Binds 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.

48-Strip-Wells

510 USD

96-Strip-Wells

725

5x96-Strip-Wells

2565

10x96-Strip-Wells

4800