12849
BCL-6 mutations in normal germinal center B cells : evidence of somatic hypermutation acting outside Ig loci .
 normal germinal center B cells, BCL-6, Ig loci
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
Answer:
 normal germinal center B cells, BCL-6, Ig loci