4761
IL-1 receptor antagonist (ra) inhibited LPS enhancement of HIV expression in GM-CSF -stimulated cells , suggesting that endogenous IL-1 was involved in LPS -mediated viral production .
 ( protein: IL-1 receptor, None) , ( cell line: GM-CSF -stimulated cells, None) , ( protein: endogenous IL-1, None) , ( protein: GM-CSF, 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:
 ( protein: IL-1 receptor, None) , ( cell line: GM-CSF -stimulated cells, None) , ( protein: endogenous IL-1, None) , ( protein: GM-CSF, None) 