Description
Principle of the assay: mouse CD22 ELISA Kit was based on standard sandwich enzyme-linked immune-sorbent assay technology. A monoclonal antibody from rat specific for CD22 has been precoated onto 96-well plates. Standards(NSO, S22-R702) and test samples are added to the wells, a biotinylated detection polyclonal antibody from goat specific for CD22 is added subsequently and then followed by washing with PBS or TBS buffer. Avidin-Biotin-Peroxidase Complex was added and unbound conjugates were washed away with PBS or TBS buffer. HRP substrate TMB was used to visualize HRP enzymatic reaction. TMB was catalyzed by HRP to produce a blue color product that changed into yellow after adding acidic stop solution. The density of yellow is proportional to the mouse CD22 amount of sample captured in plate.
Background: CD22 or cluster of differentiation-22, is a molecule belonging to the SIGLEC family of lectins. This gene is mapped to 19q13.2. It is found on the surface of mature B cells and to a lesser extent on some immature B cells. Generally speaking, CD22 is a regulatory molecule that prevents the overactivation of the immune system and the development of autoimmune diseases. It is a negative regulator of antigen receptor signaling whose onset of expression at the mature B cell stage may serve to raise the antigen concentration threshold required for B cell triggering. CD22 functions as an inhibitory receptor for B cell receptor (BCR) signalling. This gene can downmodulate signaling through the IgM and IgD B-cell receptors(BCRs), but not through the IgG BCR, because the IgG cytoplasmic tail prevents CD22 phosphorylation and actually enhances IgG-BCR signaling