11594
It has been shown that this E1B 19K protein is not necessary for viral DNA replication in human cell lines , such as HeLa and KB .
 ( protein: E1B 19K protein, None) , ( cell line: human cell lines, None) , ( cell line: KB, None) , ( cell line: HeLa, 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: E1B 19K protein, None) , ( cell line: human cell lines, None) , ( cell line: KB, None) , ( cell line: HeLa, None) 