Representative data for STAT3 (Phospho) [pY705] Multispecies InstantOne™ ELISA. A431 cells were pre-treated with 10 µM AG1478 (an EGFR kinase inhibitor), washed and unstimulated (-) or stimulated with 10 ng/mL EGF for 10 min (+). Cells were analyzed by immunoblotting (left) and InstantOne™ ELISA (right). The intensity of the band at 89 kDa as detected by immunoblot correlates with InstantOne™ ELISA absorption values.