14869
The replicative form of Epstein-Barr virus ( EBV ) DNA was studied using two lymphoblastoid cell lines , X50-7 and 6F11, which are latently infected by Epstein-Barr virus .
 ( cell line: lymphoblastoid cell lines, 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 line: lymphoblastoid cell lines, None) 