Relative re-expression of CD45RA by epitope-specific CD8⁺ T cells before and after resolution of AIM.

We investigated the CD45RA (A) and CD45RO (B) expression of EBV lytic and latent epitope-specific CD8⁺ T cells in 14 patients 12 months after the resolution of AIM. The results in panels A and B show the CD45RA and CD45RO expression, respectively, of lytic and latent epitope-specific CD8⁺ T cells that are directed to at least 3 different EBV epitopes within each group. Dotted lines in panels A and B represent the median proportion of tetramer staining cells that are positive for either CD45RA or CD45RO. Vβ usage of GLC tetramer-positive cells present in a patient after recovery from AIM was investigated next. First, PBMCs from this patient were stained with GLC-tetramer PE, CD8-tricolor, and 22 different anti-human Vβ antibodies coupled to FITC. The Vβ staining profile of the GLC-specific cells was determined on CD8-gated populations (C). Two major expansions were noted for Vβ 1 and Vβ 22. A 4-color staining analysis was then performed on the cells from this patient using CD8-tricolor, tetramer-PE, Vβ-(1 or 22) FITC, and CD45RA-cy5. Cells were gated on CD8 to show the GLC and Vβ 1 (D) and GLC and Vβ 22 (E) profiles, respectively. Cells were then gated on CD8 and GLC to determine the CD45RA expression of either Vβ 1 (F) or Vβ 22 (G) expanded populations of cells. Similar observations were obtained for 5 different patients tested.