6541
CD40 /CD40 ligand interactions play a key role in the immune responses of B lymphocytes , monocytes , and dendritic cells .
 ( protein: CD40, None) , ( cell type: dendritic cells, None) , ( cell type: B lymphocytes, None) , ( cell type: monocytes, None) , ( protein: /CD40, 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: CD40, None) , ( cell type: dendritic cells, None) , ( cell type: B lymphocytes, None) , ( cell type: monocytes, None) , ( protein: /CD40, None) 