12469
These sequences were chosen for study because mass-spectrometric analysis ( MS ) of a CTL active HPLC peptide fraction eluted from immunoaffinity precipitated HLA-A2 molecule , revealed: (a) the presence of an ion with a mass-to-charge ratio (m/z) of 793 which was more abundant than other ions of similar masses; (b) the tentatively reconstituted sequence of the ion 793 matched the sequence of peptide G76 .
 ( cell type: CTL, None) , ( protein: immunoaffinity precipitated HLA-A2 molecule, 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: CTL, None) , ( protein: immunoaffinity precipitated HLA-A2 molecule, None) 