In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
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Question:  In B - lymphoblastoid cell lines derived from two independent class II - deficient bare lymphocyte syndrome patients , we observed a drastic decrease in transcription rates of the class II genes .

Answer: class II genes


Question:  Expression of oestrogen and progesterone receptors by mast cells alone , but not lymphocytes , macrophages or other immune cells in human upper airways .

Answer: progesterone receptors


Question:  The signals regulating bcl - 6 expression are not known .

Answer:
bcl - 6