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In 1991, we demonstrated, using electrophoretic mobility shift assays , that 3 different factors (termed B1 , B2 and B3 ) with affinity for the KB-enhancer target sequence were specifically detected in nuclear extracts from HIV1 -infected monocytes and macrophages .
 protein: B2; protein: B1; DNA: KB-enhancer target sequence; cell type: macrophages; protein: B3; cell type: HIV1 -infected monocytes
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: B2; protein: B1; DNA: KB-enhancer target sequence; cell type: macrophages; protein: B3; cell type: HIV1 -infected monocytes