FIG. 2.

Flow cytometry of PBMC from an AVA-vaccinated donor, using PE-labeled PA tetramers (vertical axis) and PerCP- or allophycocyanin-labeled anti-CD4 staining (horizontal axis). (A) Frozen PBMC were thawed and incubated in the presence of PA peptides. After 12 to 14 days of expansion, the sample was stained with DRB1*1302 PA tetramers and a negative control tetramer (DRB1*1302 mortalin10A; peptide sequence, AIKGAVVGIALG). (B) Fresh PBMC were cultured with PA peptides for 12 to 14 days and stained with the specific DRB1*0404 PA 112-127 tetramer or the negative control tetramer DRB1*0404 mortlin10A. The DRB1*0404 tetramers were added in an attempt to detect a response mediated through the DRB1*0407 haplotype of the patient, since DRB1*0407 tetramers were not available. The numbers reported are percentages based on cells in the live lymphocyte gate.