2206
Reverse transcriptase-polymerase chain reaction was used to examine HB9 RNA transcripts in hematopoietic cell lines .
 HB9 RNA transcripts, hematopoietic cell lines, HB9
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:
 HB9 RNA transcripts, hematopoietic cell lines, HB9