Staining of normal human peripheral blood cells with 0.25 µg of Mouse IgG1 kappa Isotype Control Purified (Product # 14-4714-82) (open histogram) or 0.25 µg of Anti-Human CD22 Purified (filled histogram) followed by Anti-Mouse IgG FITC (Product # 11-4011-85). Cells in the lymphocyte gate were used for analysis.