Renal transplant recipients display higher frequencies of CMV-specific T cells.

(A) Frequencies of IFN-γ–producing CMV-specific CD8⁺ T cells (y-axis, IFN-γ⁺CD69⁺ cells as percentage of CD8⁺ T cells) in CMV-seropositive HLA-A2⁺ healthy individuals (○) and CMV-seropositive HLA-A2⁺ renal transplant recipients (●). Frequencies of these CMV-specific CD8⁺ T cells were higher in renal transplant recipients (Mann-Whitney, P = .0082). (B) Frequencies of NLVPMVATV–HLA-A2.1 tetramer binding CD8⁺ T cells (y-axis, percentage of CD8⁺ T cells) in CMV-seropositive HLA-A2⁺ control individuals without immunosuppression (○) and in CMV-seropositive HLA-A2⁺patients after renal transplantation (●). Frequencies of these CMV-specific CD8⁺ T cells were higher in renal transplant recipients (Mann-Whitney, P = .0056). (C) Frequencies of CD27⁻ cells among CMV-specific CD8⁺ T cells (y-axis, percentage of tetramer-positive CD8⁺ T cells) in CMV-seropositive HLA-A2⁺ control individuals (○) and renal transplant recipients (●). Frequencies of CD27⁻cells among tetramer-positive CD8⁺ T cells were statistically significantly different in renal transplant recipients compared to control individuals (Mann-Whitney,P = .0216).