... Given the findings of this study, the presence and persistence of IgG and IgE anti-influenza anti-bodies in the serum from those with normal and ele-vated levels of IgE are understandable. ... anti-influenza immunity and their memory responses. Further studies are necessary to elucidate the role of immunoglobulins in influenza infection and to determine possible functional roles of ... history of infection or vaccination. 4. Cytokines in serum. Similar levels of IL-2, IFN-γ, IL-4, and IL-10 cy-tokines were detected in serum of vaccinated com-pared with non vaccinated...