Phenotypic and functional mapping of the CD2 antigen on pDCs. CD14⁺ Mx's were enriched from PBMCs by negative selection and were negative for CD3, CD19, and CD56. The remaining population was more than 93% positive for CD14 (A-D). The Mx cells were further stained with anti-T11₁ (A), anti-T11₂ (B), or anti-T11₃ (C-D) mAbs. Mx's (▴) and CD3⁺ T cells (•) were incubated sequentially with anti-T11₂, anti-T11₃, and goat antimouse mAbs (E), and changes in intracellular Ca²⁺ were measured. Time represents (1) the addition of T11₂, (2) the addition of anti-T11₃, (3) the addition of goat antimouse IgG, and (4) the addition of A23187 Ca²⁺ ionophore. The results are representative of 3 experiments.