Sandwich ELISA quantitative detection kit for Human CD23/FCER2 in cell culture supernates, serum, plasma (heparin, EDTA) and urine.CD23, also known as Fc epsilon RII, or Fc RII, is the "low-affinity" receptor for IgE, an antibody isotype involved in allergy and resistance to parasites, and is important in regulation of IgE levels. There are two forms of CD23 CD23a and CD23b. CD23a is present on follicular B cells, whereas CD23b requires IL-4 to be expressed on T-cells, monocytes, Langerhans cells, eosinophils, and macrophages. As part of a mapping of multiple probes to specific bands on chromosome 19 by fluorescence in situ hybridization, the FCE2 gene was assigned to 19p13.3. CD23(FCE2) is a key molecule for B-cell activation and growth. It is the low-affinity receptor for IgE. The truncated molecule can be secreted, then functioning as a potent mitogenic growth factor.