7216
Human alveolar macrophages are markedly deficient in REF-1 and AP-1 DNA binding activity .
 REF-1, AP-1, Human alveolar macrophages
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:
 REF-1, AP-1, Human alveolar macrophages