Stimulated cytokine responses from PBMCs. PBMCs from patient P (triangles) were challenged with indicated stimuli in vitro on multiple occasions over 3 years, and the cytokine production compared with PBMCs from healthy persons (circles) (n = 50, not age or sex matched). (A) IL-1β production was significantly increased after stimulation with pan-T cell and viral mimic (PHA and poly I:C). (B) IL-8 production in response to PHA, phorbol 12-myristate 13-acetate (PMA), or ssRNA was elevated compared with controls. (C) Production of tumor necrosis factor-α (TNFα) is also markedly elevated (P < .001) in response to PHA. Other cytokines measured were either not significantly different or were reduced compared with the healthy controls. LPS indicates lipopolysaccharide; ION, ionomycin; and SAC, Staphylococcus aureus Cowan I.