6593
We thus propose that during an in vivo chronic response, a narrow range of avidity of the TCR -CD8 complex conditions long-term clonotype persistence, and that the level of CD8 contribution is adjusted to keep clonotypes with variable TCR affinities within this avidity window .
 ( protein: CD8, None) , ( protein: TCR, None) , ( protein: TCR, None) , ( protein: TCR -CD8 complex, 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: CD8, None) , ( protein: TCR, None) , ( protein: TCR, None) , ( protein: TCR -CD8 complex, None) 