Figure 4

Inhibition of KLK6 activity by IgYs. The activity was measured in the absence (A) and presence of IgYs at increasing molar ratios of IgYs:rKLK6 equal to 1:1, 20:1 and 30:1 (B, C and D, respectively). Then, the trypsin substrate N-benzoyl-L-arginine ethyl ester (BAEE) was added and the change in absorbance at A254 was measured relative to time for 3 min. The corresponding changes in the absorbance at A254 were normalized and expressed % of the rKLK6 without addition of the antibodies. IgYs could inhibit rKLK6 only moderately as 61% of its activity remained at a molar ratio as high as 30:1, while the E24 mouse monoclonal control could extinguish 60% of the activity at 1:1. Rates of hydrolysis of the BAEE substrate by rKLK6 are shown. BAEE was used at 250 μΜ and rKLK6 at 12 nM.