1X10^6 BALB/c mouse splenocytes were surface stained with 0.5 ug Rat IgG2b Isotype Control (65211-1-Ig, Clone: LTF-2) (blue) and Fluorescein (FITC)-conjugated Affinipure Goat Anti-Rat IgG(H+L) at dilution of 1:1000, or with 0.5 ug Anti-Mouse CD4 (65104-1-Ig, Clone: GK1.5) (red) and Fluorescein (FITC)-conjugated Affinipure Goat Anti-Rat IgG(H+L) at dilution of 1:1000. Cells were not fixed.