11595
We reported here that the E1B 19K mutant viruses were unable to replicate efficiently in a monocyte cell line , U937 .
 U937, E1B 19K, monocyte cell line
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 U937, E1B 19K, monocyte cell line