Description: This High Sensitivity ELISAs enables the analysis of Interleukin- 4 in low concentrations from serum, plasma, or cell culture samples.
eBioscience High Sensitivity ELISA Kits offer accurate quantification below conventional ELISA limits. This is made possible by ther inherent design by amplifying the signal generated by the enzyme horseradish peroxidase (HRP) and the colorimetric-detectable substrate tetramethylbenzidin (TMB) based on Tyramide Signal Amplification (TSA) technology*.
IL-4 mediates its function by binding to receptors expressed on target cells. The IL-4 receptors exhibit an affinity of approximately 10-10 M.
Receptors exist on freshly prepared B and T lymphocytes and macrophages, as well as on various cell lines including lymphoid cells, mast cell lines, a variety of other hematopoietic cell lines, fibroblasts and stromal cell lines. On T and B cells, receptors are present in low numbers (appr. 400), which are reported to be upregulated by IL-2 and IL-4.
IL-4 is produced by a particular subset of T helper cells, the TH2 cells. These cells tend to make a specific set of lymphokines including IL-4, IL-5, IL-6, IL-10, IL-13 and GM-CSF and fail to produce IL-2, IFN-gamma, and lymphotoxin (TNF-beta). Apart from T cells, it has been shown that mast cells can produce IL-4.
IL-4 exerts numerous effects on various hematopoietic cell types. On B cells, IL-4 promotes immunological class switching to IgE and IgG1 isotypes and upregulates MHC class II and CD23 expression. It can promote survival, growth, and differentiation of both T and B lymphocytes, mast cells, and endothelial cells.
In addition, IL-4 can inhibit the production of TNF, IL-1, and IL-6 by macrophages.
*High Sensitivity ELISAs are based on a patent from PerkinElmer LAS, patent number 5,731,158; 5,583,001; 5,196,306.
