Differential sensitivity of DC types to nucleotides. Nucleotide-induced Ca²⁺ signaling of MoDCs, CD1a⁺ dermal DCs, CD1c⁺ PBDCs, and IL-3R⁺ PDCs was analyzed by flow cytometry. After establishing a baseline for 10 to 30 seconds, nucleotides were added at the indicated concentrations. (A) Each lane represents Ca²⁺ transients induced in DCs from the same donor and is representative of at least 4 separate experiments (for CD1a⁺ dermal DCs, n = 1). (B) Ca²⁺ signaling of MoDCs and CD1c⁺ PBDCs in response to 100 μM BzATP in the absence (solid line) or presence (dotted line) of 0.5 mM EDTA.