Serum IgE Levels and In Vitro Production of IL-2,IL-4,and IFN-γ in Children with Down's Syndrome

In nine children and one young adult with Down's syndrome (DS), lymphocyte phenotype, total serum IgE levels, and in vitro mononuclear cell (PBMC) proliferative responses to phytohemagglutinin (PHA) plus phorbol myristate acetate (PMA) and human recombinant interleukin-2 (hrIL2), and production of interleukin-2 (IL2), interleukin-4 (IL4), and interferon-gamma (IFNγ) were evaluated. The results showed a normal PBMC proliferative response to mitogens and a normal in vitro production of IL4 and IFNγ, while IL2 production was significantly decreased (p < 0.05). CD8+ cells were significantly increased (p < 0.01) and in five of eight patients with DS the IgE serum levels were lower than those in normal controls. IL4 production was lower in patients with DS with low IgE levels than in those with normal levels of serum IgE.