13970
When NK cells were costimulated with IL-13 and IL-2 , IL-13 generally resulted in two types of reactivity: IL-13 synergized with IL-2 to stimulate IFN-gamma production or it modestly inhibited IL-2 -mediated IFN-gamma production .
 IFN-gamma, IFN-gamma, IL-13, IL-2, IL-13, NK cells, IL-2, IL-2, IL-13
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:
 IFN-gamma, IFN-gamma, IL-13, IL-2, IL-13, NK cells, IL-2, IL-2, IL-13