1662
Second, by high stringency Northern blotting and in situ hybridization , TCF-1 expression was shown to be confined to the thymus and to the T cell areas of the spleen .
 protein: TCF-1
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: TCF-1