7268
In the culture system reported here, (1) the growth factor ( GF ) stimulus induces cord blood (CB) progenitor cells to proliferate and differentiate/mature exclusively along the erythroid lineage ; (2) this erythropoietic wave is characterized by less than 4% apoptotic cells; (3) asymmetric divisions are virtually absent, ie, nonresponsive hematopoietic progenitors with no erythropoietic potential are forced into apoptosis ; (4) the system is cell division controlled (cdc), ie, the number of divisions performed by each cell is monitored.
 ( cell type: cord blood (CB) progenitor cells, None) , ( cell type: erythroid lineage, None) , ( cell type: progenitor cells, None) , ( cell type: hematopoietic progenitors, None) , ( protein: GF, None) , ( protein: growth factor, 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 type: cord blood (CB) progenitor cells, None) , ( cell type: erythroid lineage, None) , ( cell type: progenitor cells, None) , ( cell type: hematopoietic progenitors, None) , ( protein: GF, None) , ( protein: growth factor, None) 