Time- and concentration-dependent regulated upon activation, normal T-cell expressed and secreted (RANTES) induction by human pulmonary arterial endothelial cells in response to IgG purified from anti-endothelial cell antibodies (AECA)-positive, AECA-negative, and healthy control sera. (A) Endothelial cells were incubated for up to 48 h with IgG (100 µg/mL) purified from AECA-positive, AECA-negative, and healthy control sera; (B) endothelial cells were incubated for 24 h with 2.5, 10, 50, 100, and 200 µg/mL IgG purified from AECA-positive, AECA-negative, and healthy control sera.