10807
Previous reports have suggested the CD28 stimulation contributes to the activation of the IL-2 promoter by up-regulating the activity of several transcription factors , including AP-1 and nuclear factor-kappaB ( NF-kappaB )/ Rel family members as well as an uncharacterized transcription factor called CD28 response complex.
 IL-2, CD28, nuclear factor-kappaB ( NF-kappaB )/ Rel family members, transcription factors, CD28, Rel, uncharacterized transcription factor, IL-2 promoter, nuclear factor-kappaB, NF-kappaB, 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:
 IL-2, CD28, nuclear factor-kappaB ( NF-kappaB )/ Rel family members, transcription factors, CD28, Rel, uncharacterized transcription factor, IL-2 promoter, nuclear factor-kappaB, NF-kappaB, AP-1