13071
In contrast, minimal or no activation of Stat3beta was observed, suggesting that IL-2 and IL-15 predominantly activate Stat3alpha in human CD4(+) T cells .
 ( cell type: human CD4(+) T cells, None) , ( protein: Stat3beta, None) , ( protein: Stat3alpha, None) , ( protein: IL-15, None) , ( protein: IL-2, 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 type: human CD4(+) T cells, None) , ( protein: Stat3beta, None) , ( protein: Stat3alpha, None) , ( protein: IL-15, None) , ( protein: IL-2, None) 