4862
Addition of r-hTBP-1 to U1 cells during the last 4 h of a 24 h incubation with PMA still inhibited p24 antigen production by 15%.
 ( protein: r-hTBP-1, None) , ( cell line: U1 cells, None) , ( protein: p24 antigen, 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: r-hTBP-1, None) , ( cell line: U1 cells, None) , ( protein: p24 antigen, None) 