5511
Here, we studied the role of serine /threonine phosphatases in STAT3 signaling in human antigen-specific CD4(+) T cell lines and cutaneous T cell lymphoma lines , expressing a constitutively activated STAT3 .
 ( cell line: cutaneous T cell lymphoma lines, None) , ( cell line: human antigen-specific CD4(+) T cell lines, None) , ( protein: serine /threonine phosphatases, None) , ( protein: STAT3, None) , ( protein: STAT3, 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: cutaneous T cell lymphoma lines, None) , ( cell line: human antigen-specific CD4(+) T cell lines, None) , ( protein: serine /threonine phosphatases, None) , ( protein: STAT3, None) , ( protein: STAT3, None) 