Baboon LCV- and bCMV-specific (IFN-γ–producing) CD4 T cells include YFP⁺ cells originating from grafted hematopoietic cells. Blood mononuclear cells were stimulated with autologous bLCV-transformed B cells (B) or bCMV lysate (D). As controls, the mononuclear cells were stimulated with medium only (A) or with uninfected MRC5 cell lysate (C). In this example, cells from animal M00093 were stimulated with medium only or bLCV (A-B), and cells from animal J00116 were stimulated with MRC5 or bCMV lysate (C-D). Dot plots shown here were gated on CD3⁺CD4⁺ lymphocytes. The same number of dots is displayed for the stimulated condition and the control condition. Numbers displayed represent percentages of cells in respective quadrants.