13734
We found very little detectable activation of AP-1 , as assessed in a gel shift assay , in alveolar macrophages , whereas monocytes showed a substantial activation of AP-1 by PMA .
 alveolar macrophages, monocytes, AP-1, AP-1
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:
 alveolar macrophages, monocytes, AP-1, AP-1