1608
Viral gene expression may be reactivated by stimulation of the cells with LPS or cytokines such as TNF-alpha in vitro.
 protein: TNF-alpha; protein: cytokines
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: TNF-alpha; protein: cytokines