13948
A small population of UT-7/GM cells positively stained for hemoglobin ( Hb ) after a 7-day exposure to TPO .
 ( cell line: UT-7/GM cells, None) , ( protein: Hb, None) , ( protein: hemoglobin, None) , ( protein: TPO, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( cell line: UT-7/GM cells, None) , ( protein: Hb, None) , ( protein: hemoglobin, None) , ( protein: TPO, None) 