1149
On the basis of Western blotting experiments using antibodies to kappa B/Rel family proteins , the kappa B-binding activity constitutively expressed in T cells from RCC patients is composed mostly of the NF-kappa B1 ( p50 ) subunit .
 ( cell type: T cells, None) , ( protein: kappa B/Rel family proteins, None) , ( protein: p50, None) , ( protein: NF-kappa B1 ( p50 ) subunit, None) , ( protein: antibodies, 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: T cells, None) , ( protein: kappa B/Rel family proteins, None) , ( protein: p50, None) , ( protein: NF-kappa B1 ( p50 ) subunit, None) , ( protein: antibodies, None) 