13068
It is unknown which Stat3 isoform (s) is activated in response to interleukin (IL)-2 and IL-15 .
 ( protein: interleukin (IL)-2, None) , ( protein: Stat3, None) , ( protein: IL-15, None) , ( protein: Stat3 isoform, 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: interleukin (IL)-2, None) , ( protein: Stat3, None) , ( protein: IL-15, None) , ( protein: Stat3 isoform, None) 