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Purified OTF1 from HeLa cells and OTF1 and OTF2 from B cells bound to identical sequences within the heavy-chain promoter .
 protein: OTF1; cell line: HeLa cells; cell type: B cells; DNA: heavy-chain promoter; protein: OTF2; protein: OTF1
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 protein: OTF1; cell line: HeLa cells; cell type: B cells; DNA: heavy-chain promoter; protein: OTF2; protein: OTF1