Bimodality in the human Vγ9Vδ2 T cell response to EBV in vivo. (A) Scatter plots represent the absolute numbers of NK cells (yellow), CD8 T cells (light violet), CD4 T cells (dark violet), and B cells (green) in peripheral blood of children experiencing acute IM (circles) and healthy children (triangles). EBV⁻ healthy children are indicated by black triangles. Mean values are given. Statistical significance in the difference between IM and healthy children was assessed using the unpaired Student’s t test (*, P = 0.04; ***, P ≤ 0.0005; ns, nonsignificant). (B) Scatter plots represent the absolute numbers of iNKT cells (dark blue), Vδ1 T cells (light blue), and Vγ9Vδ2 T cells (orange) in peripheral blood of children experiencing acute IM (circles) and healthy children (triangles). EBV⁻ healthy children are indicated by black triangles. Statistical significance in the difference between IM and healthy children was assessed using the unpaired Student’s t test (***, P < 0.0001; ns, nonsignificant). (C) Scatter plots represent the proportion of Vγ9Vδ2 T cells in peripheral blood of children experiencing acute IM (circles), children at 6 mo after the diagnosis of IM (crossed circles), healthy children (triangles), and healthy adults (diamonds). EBV⁻ healthy children are indicated by black triangles. (D) Scatter plots represent the age of children experiencing acute IM (circles) and healthy children (triangles). Children who exhibited high proportions of Vγ9Vδ2 T cells are indicated in orange.