6402
In addition, we evaluated the effect of dexamethasone on phorbolmyristate-acetate -stimulated IL-1 receptor antagonist secretion by the human monocytic cell line U937 .
 ( cell line: human monocytic cell line U937, None) , ( protein: IL-1, None) , ( protein: IL-1 receptor, 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: human monocytic cell line U937, None) , ( protein: IL-1, None) , ( protein: IL-1 receptor, None) 