ADAMTS13 activity was reduced in the incubation time and temperature-dependent manners. (A, B &C) Clear evidence of a time-dependent inhitition was observed either at 37°C, 38°C, or 39°C. *P < 0.05, **P < 0.01, ***P < 0.001. (D) A temperature-dependent inhibition was observed. ADAMTS13 activity was significantly decreased at 38°C and 39°C incubation temperature, compared to 37°C for each incubation time except for 24 hr of 38°C compared to 37°C (NS = Not significant). All results represent mean ± SEM.