Dose response curve of HRP conjugated Rabbit Anti-Human IgG4 mAb measured by ELISA. 1 µg/mL of various immunoglobulins were coated to 384-well plate., blank wells without protein were used as negative control (NC). The coated plate was blocked and subsequently incubated with 25 µL of HRP conjugated Rabbit Anti-Human IgG4 mAb in a 2 fold serial dilution from 1 μg/mL to 7.8*10^-3 pg/mL, incubation was performed at room temperature for 1 hour. The ELISA result demonstrated that Rabbit Rabbit Anti-Human IgG4 has highly specific recognition of Human IgG4 while no or minimal cross reactivity to Human IgG1、Human IgG2、Human IgG3、Human IgM、Human IgE、Human IgD.