Vδ2^neg γδ T cells represent a major population of circulating CD16-expressing cells in individuals persistently infected with HCMV. Six-color staining with mAbs directed against CD3, Vδ2, TCRγδ, CD16, CD45, and NKp46 was performed on PMBC from 10 HCMV-infected KTRs to analyze the composition of the CD16^pos lymphocyte compartment. (A) Percentage of each subset within the CD45⁺CD16⁺ cell population: NK cells (CD3⁻CD45⁺NKp46⁺), αβ T cells (CD3⁺CD45⁺TCRγδ-Vδ2-), Vδ2^pos γδ T cells (CD3⁺CD45⁺pan-TCRγδ⁺Vδ²⁺), and Vδ2^neg γδ T cells (CD3⁺CD45⁺TCRγδ⁺Vδ2-). Data are expressed as medians (range). (B) Inter-individual variability in CD45⁺CD16⁺ subsets for each KTR. (C) CD16 expression on each CD45⁺CD16⁺ subset as determined by median fluorescence intensity (MFI). Data of 1 representative KTR are presented. (D) Blood from HCMV-seropositive KTRs (n = 6) and healthy volunteers (n = 3) was incubated with mAbs directed against CD3, CD8, and CD16 as well as with pp65-HLA-A2 dextramers. Staining from 1 representative KTR is presented.