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We have found that the HTLV-1 transactivator protein , tax , acts as a costimulatory signal for GM-CSF and IL-2 gene transcription , in that it can cooperate with TCR signals to mediate high level gene expression .
 protein: tax; protein: HTLV-1 transactivator protein; protein: TCR
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: tax, HTLV-1 transactivator protein, TCR 
Answer:
 protein: tax; protein: HTLV-1 transactivator protein; protein: TCR