5663
While the MHC-peptide complexes formed with the native peptide are stable, complexes formed with the Ala -substituted peptide had a functional t1/2 of less than 4 hr at neutral pH .
 ( protein: MHC-peptide complexes, 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: MHC-peptide complexes, None) 