Human CD81 ELISA Kit | EL-213-3481

Cat. No: EL-213-3481

$859.99 USD

96 wells

1
Target proteinCD81
Gene ID975
ReactivityHuman
Detection range0.32-20 ng/mL
Sample typetissue homogenates, cell lysates and other biological fluids
Sample volume100 µL
Assay time3h 20min
PrecisionIntra-assay CV <8%. Inter-assay CV <10%
ComponentsPre-Coated Microplate - 12 strips x 8 wells (4°C/-20°C)
Standard (Lyophilized) - 2 vials (4°C/-20°C)
Biotinylated Antibody (100×) - 120 μL (4°C/-20°C)
Streptavidin-HRP (100×) - 120 μL (4°C/-20°C)
Standard/Sample Diluent Buffer - 20 mL (4°C/-20°C)
Biotinylated Antibody Diluent - 12 mL (4°C/-20°C)
HRP Diluent - 12 mL (4°C/-20°C)
Wash Buffer (25×) - 20 mL (4°C/-20°C)
TMB Substrate Solution - 10 mL (4°C/-20°C (store in dark))
Stop Reagent - 6 mL (4°C/-20°C)
Plate Covers - 2 pieces (RT)
Storage4°C/-20°C

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Safety Warning: Research Use Only. Not for diagnostic use.

This assay uses a sandwich enzyme immunoassay format to quantify CD81 (TAPA1) in biological samples.

Introduction

CD81, also called TAPA-1, is a small tetraspanin membrane protein with four hydrophobic transmembrane segments that assembles into specialized “tetraspanin-enriched microdomains,” platforms that cluster partner receptors together at the cell surface. On B lymphocytes it escorts the CD19 co-receptor to these microdomains, allowing the CD19/CD21 complex to associate efficiently with the B-cell receptor and lowering the amount of antigen needed to trigger clonal expansion and antibody secretion; on T cells it helps position the CD3 signaling complex at the immune synapse, contributing to costimulation and skewing responses toward a T-helper-2 phenotype. The same tetraspanin scaffold also governs several cell-fusion events, promoting sperm-egg fusion during fertilization while restraining unwanted fusion of macrophages into giant cells and of progenitor cells into bone-resorbing osteoclasts. Clinically, CD81 doubles as an entry receptor hijacked by hepatitis C virus in liver cells, and inherited loss-of-function changes in the gene cause a primary antibody-deficiency syndrome marked by impaired B-cell differentiation and recurrent bacterial infections.

Principle of the Assay

This kit employs a sandwich enzyme immunoassay to measure Human CD81 (TAPA1). Microtiter plate wells are pre-coated with a capture antibody specific to Human TAPA1, which binds the target analyte present in standards or samples added to the wells. A biotin-conjugated detection antibody, also specific to Human TAPA1, is then introduced to form a sandwich complex on the plate. Avidin conjugated to horseradish peroxidase (HRP) is subsequently added to each well and binds the biotin-conjugated detection antibody. Upon addition of TMB substrate solution, a colorimetric signal develops only in wells where Human TAPA1, the biotin-conjugated antibody, and the avidin-HRP conjugate are all present. The enzymatic reaction is stopped by addition of a sulphuric acid stop solution, and absorbance is measured spectrophotometrically at 450 nm (± 10 nm). Human TAPA1 concentration in each sample is determined by comparing sample absorbance values against a standard curve.