1X10^6 C57BL/6 mouse splenocytes were surface stained with 0.5 ug Anti-Mouse CD3 (65077-1-Ig, Clone: 17A2) and FITC anti-Rat IgG2b Antibody at dilution 1:100, or 0.5 ug Rat IgG2b Isotype Control (LTF-2) (65211-1-Ig, Clone: LTF-2) and FITC anti-Rat IgG2b Antibody at dilution 1:100. Cells were co-stained with APC Anti-Mouse CD4 (GK1.5) (APC-65104, Clone: GK1.5). Cells were not fixed.