9821
In addition, we show that TNF-alpha is a potent costimulatory factor of the very immature CD34+Thy-1+ CB subset .
 ( protein: TNF-alpha, None) , ( cell line: immature CD34+Thy-1+ CB subset, 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:
 ( protein: TNF-alpha, None) , ( cell line: immature CD34+Thy-1+ CB subset, None) 