12672
Unlike IL-12 , which acts only on Th1 cells , IFN-alpha /beta can activate Stat4 not only in human Th1 , but also in Th2 cells .
 ( protein: Stat4, None) , ( cell type: Th2 cells, None) , ( cell type: Th1 cells, None) , ( protein: IFN-alpha /beta, None) , ( protein: IL-12, None) , ( cell type: human Th1, None) , ( protein: IFN-alpha, 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: Stat4, None) , ( cell type: Th2 cells, None) , ( cell type: Th1 cells, None) , ( protein: IFN-alpha /beta, None) , ( protein: IL-12, None) , ( cell type: human Th1, None) , ( protein: IFN-alpha, None) 