p110δ inhibition blocks recall responses from disease samples. (A-B) PBMCs from atopic persons were pulsed with house dust mite antigen in the presence of DMSO alone or IC. After 6 days, IL-5 (A) and IL-13 (B) were measured. (C-F) Mononuclear cells from synovial fluid of ReA patients were stimulated with anti-CD3 in the presence of DMSO alone, IC, or CS. Proliferation (C), IFN-γ (D), IL-17 (E), and TNF-α (F) production were measured at 72 hours. Each dot represents an individual donor. To calculate P values, Student t test was used to compare DMSO alone with CS, and 1-way repeated-measures analysis of variance was used to compare DMSO alone with IC. *.01 < P < .05; **.001 < P < .01; ***P < .001. Percentage inhibition was calculated for each donor to determine the range of sensitivity in the population, and median values are shown below the graph.