4260
Interestingly, in CIITA -transfected cell hybrids , cell surface expression of the human HLA-DQ heterodimer was not observed.
 ( cell line: CIITA -transfected cell hybrids, None) , ( protein: CIITA, None) , ( protein: human HLA-DQ heterodimer, 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: CIITA -transfected cell hybrids, None) , ( protein: CIITA, None) , ( protein: human HLA-DQ heterodimer, None) 