The 500A2 monoclonal antibody specifically binds to the 25-kDa ε chain of the T-cell receptor-associated CD3 complex expressed on mouse thymocytes, mature T lymphocytes, and NKT cells. Plate-bound and soluble forms of the 500A2 antibody can activate T cells in vitro. Activation of a mouse T-cell clone by the 500A2 antibody can be blocked by Fab fragments of the GK1.5 anti-CD4 antibody. This suggests that the 500A2 antibody may bind an epitope on CD3e close to a site at which CD4 associates with the T-cell receptor. The 500A2 antibody reportedly does not to crossreact with rat leukocytes.
The antibody is conjugated to BD Horizon™ V500, which has been developed for use in multicolor flow cytometry experiments and is
available exclusively from BD Biosciences. It is excited by the Violet laser with an Ex max of 415 nm and Em Max at 500 nm. BD Horizon V500 conjugates emit at a similar wavelength to Amcyan yet exhibit reduced spillover into the FITC channel. For more information on BD Horizon V500, visit bdbiosciences.com/colors.
When compensating dyes in this spectral range (such as Horizon™ V500 and AmCyan), the most accurate compensation can be obtained using single stained cellular controls. Due to spectral differences between cells and beads in this channel, using BD CompBeads can result in spillover errors for V500 and AmCyan reagents. Therefore, the use of BD CompBeads or BD CompBeads Plus to determine spillover values for these reagents is not recommended. Different V500 reagents (e.g. CD4 vs. CD45) can have slightly different fluorescence spillover therefore, it may also be necessary to use clone specific compensation controls when using these reagents.