11663
In this paper, we demonstrate that the activation of NF-kappaB by LPS in a promonocytic cell line ( U937 ) followed a rather slow kinetics, depending on the rate of IkappaB-alpha inhibitor hydrolysis .
 ( cell line: U937, None) , ( protein: NF-kappaB, None) , ( protein: IkappaB-alpha, None) , ( cell line: promonocytic cell line, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( cell line: U937, None) , ( protein: NF-kappaB, None) , ( protein: IkappaB-alpha, None) , ( cell line: promonocytic cell line, None) 