14683
Gel-shift analysis reveals the constitutive presence of nuclear factors in resting PBL that bind to the proximal AP-1 site of the IL-2 promoter and that contain immunoreactive c-Jun but not c-Fos protein.
 resting PBL, c-Jun, PBL, IL-2 promoter, proximal AP-1 site, c-Fos
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:
 resting PBL, c-Jun, PBL, IL-2 promoter, proximal AP-1 site, c-Fos