Our immune system is a powerful defense mechanism against infection, however different variables can cause our immune response to work for or against us. CD3 (cluster of differentiation 3) is one component of our immune signal response that is composed of four distinct chains (CD3-g, CD3-e, CD3-s and the zeta chain). These chains associate with a molecule known as the T-cell receptor (TCR) to comprise the TCR complex. Broadly, CD3 is expressed in pro-thymocytes (stem cells where T cells arise in the thymus) in order to mediate signals that are critical for T cell development and function in response to foreign pathogens.
The CD3 (OKT3 Clone) antibody (Cat# NBP2-24867) specifically reacts with an epitope on the epsilon subunit, which plays a vital role in the creation of new T cells. OKT3 has been found to illustrate immunosuppressive properties and defects in this gene lead to immunodeficiency. Given that CD3 is required for T-cell activation, a multitude of targets are being investigated as immunosuppressant therapies for various autoimmune diseases. In addition, CD family proteins are also used to measure efficiency of immune response in reaction to stimuli and changes in microenvironments.
CD3 Antibody (OKT3) [Azide Free] [NBP2-24867] - Analysis using the Alexa Fluor (R) 488 conjugate of NBP2-24867. Detection of CD3 expression in hPBMc's gated to lymphocyte population at 1 x 10^6 cells/ml. Cells were stained with NBP2-24867AF488 (orange) conjugate at a 1:500 dilution. Results are shown with mIgG2 (AF488 conjugate) isotype control (blue).
It has been shown that repeated cocaine use results in a heightened impact of HIV infection. Kim et al followed the immune response of HIV infected humanized BLT mice after receiving cocaine administration with a CD3 (OKT3 Clone) antibody that helped to measure T cell activation and plasma cytokine levels. Whitehurst et al actually used 5ug/ml of a CD3 (OKT3 Clone) antibody to administer directly to both EBV+ and EBV- mice for 14 days. Their results showed that knockout of Epstein-Barr Virus BPLF1 slows B Cell Transformation by use of a CD3 antibody to measure T cells and a CD20 antibody to measure B cells. BPLF1 of Epstein-Barr virus (EBV) is involved in viral infection and also contributes to processes that affect viral infectivity, viral DNA replication, DNA repair, and immune evasion. Elucidating EBV’s global effect on immune response was a significant advancement in elucidating this pathway.
Furthermore, Gill T et al used a CD3 (OKT3 Clone) antibody to study T cell receptor initiated signal transduction. Specifically, Gill’s research group used the CD3 (OKT3 Clone) antibody to measure TCR engagement in Western Blot on WT Jurkat cells, Mn-SOD overexpressed Jurkat cells, and Cu,Zn-SOD overexpressed Jurkat cells. They found that increased production of H2O2 due to overexpression of Mn-SOD changes the membrane tyrosine phosphorylation at the TCR and selectively enhances the JNK/cJun second messenger pathway.
Overall, the specific CD3 (OKT3 Clone) antibody is being used to pinpoint specific interactions at the TRC and subsequent effects on T cell development, activation, and function in reaction to external and endogenous stimulants.