3329
They also demonstrate for the first time the occurrence of T cell responses against EBV transactivating factors , which might be central in the control of virus reactivation .
 ( protein: EBV transactivating factors, 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: EBV transactivating factors, None) 