7863
On first encounter with antigen, naive CD4+ T helper (Th) cells differentiate into cytokine -producing effector cells .
 ( cell type: naive CD4+ T helper (Th) cells, None) , ( protein: cytokine, None) , ( cell line: cytokine -producing effector cells, 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: naive CD4+ T helper (Th) cells, None) , ( protein: cytokine, None) , ( cell line: cytokine -producing effector cells, None) 