11443
These results demonstrate that Itk plays a role in IL-2 production , indicating a critical involvement of Itk in the initial stage of T cell activation by mediating signals from the TCR/CD3 complex , CD2 , and CD28 .
 ( protein: CD2, None) , ( protein: CD28, None) , ( protein: Itk, None) , ( protein: IL-2, None) , ( protein: Itk, None) , ( protein: TCR/CD3 complex, 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: CD2, None) , ( protein: CD28, None) , ( protein: Itk, None) , ( protein: IL-2, None) , ( protein: Itk, None) , ( protein: TCR/CD3 complex, None) 