Antigen details
Reactivity:? The CD3 monoclonal antibody is directed against the CD3- antigen (T3-antigen), which is expressed on human T lymphocytes. The monoclonal antibody reacts with 80-90% human peripheral T lymphocytes and medullary thymocytes. The monoclonal antibody does not react with B-cells, monocytes, granulocytes and platelets. The monoclonal antibody is mitogenic for resting T lymphocytes and it blocks the cytolytic activity of CTL clones.
This CD16 PE, clone 3G8 monoclonal antibody reacts with human and non-human primate CD16, which is also known as the low-affinity FcγRIII. CD16 exists as two distinct isoforms, FcγRIIIA and FcγRIIIB. In humans, FcγRIIIA is expressed as a polypeptide-anchored form on monocytes, macrophages, and lymphocytes such as NK cells. T and B cells do not express this Fc receptor. FcγRIIIB is also detected on neutrophils as a GPI-anchored form. Expression of CD16 on lymphocytes and monocytes is similar in non-human primates. However, while CD16 is not found on neutrophils in macaques and baboons, this receptor is detected on these cells in sooty mangabeys. Binding of IgG leads to activation of signal transduction pathways, resulting in antibody-dependent cell-mediated cytotoxicity (ADCC), phagocytosis, cytokine release, and antigen presentation
Regarding CD56, expression of neural cell adhesion molecules (N-CAM) provides neurons with a means of attaching to and interacting with other cells and the extracellular matrix. Alternative splicing of N-CAM mRNA results in several N-CAM isoforms. The three major isoforms are referred to as 180 kD, 140 kD, and 120 kD. Individual isoforms undergo various post-translational modifications, including the addition of polysialic acid residues to embryonic forms. The highly polysialylated forms of N-CAM present in embryos and neonates are lost during maturation and replaced by less-polysialic ?acid-laden mature forms of N-CAM. The functional significance of alternative forms of N-CAM remains to be fully elucidated.
Specificity: The CD3 antibody recognizes 22/26/30 kD MW lymphocyte surface molecules associated with the T cell antigen receptor complex. Reacts with 85% of peripheral blood T lymphocytes, 70% of thymocytes, the majority of T cell chronic lymphocytic leukaemias, Sezary leukaemias and approximately 70% of acute lymphoblastic leukaemias of T cell origin. CD16 monoclonal antibody has been reported to have several functional activities, including inhibition of cytotoxic ability, activation of cell signaling, and NK cell depletion?in vivo. Moreover, the 3G8 antibody clone has been demonstrated to work on capuchin monkey, chimpanzee, common marmoset, cynomologous monkey, hamadyras baboon, olive baboon, pigtailed macaque, rhesus, and squirrel monkey.
The CD56 antigen is a 175-185kDa isoform of the neural cell adhesion molecule (NCAM). It is expressed by lymphocytes mediating non-MHC restricted cytotoxicity and is present on some neural tissues and tumors. It is expressed on natural killer (NK) Cells and a subpopulation of T lymphocytes. NK cells make up approximately 10-25% of peripheral blood lymphocytes.?
