Anisakis simplex Excretion/Secretion Antigens Abolish the Anaphylactic Response in Allergic Mice.

Introduction: Helminths' products modulate the allergic response. We aimed to analyze the inhibitory effect of Ascaris lumbricoides, Anisakis simplex, and A. simplex excretion/secretion (E/S) antigens in a peanut-induced anaphylaxis mouse model.

Methods: Four groups of nine C3H/HeOuJ mice were weekly sensitized with intraperitoneal (i.p.) peanut extract (P) for 3 weeks. Concomitantly, first group was daily treated with i.p. A. simplex somatic extract, second group with A. lumbricoides somatic extract, third group with A. simplex E/S extract (P/AK-ES), and a fourth group with saline (P/saline). Nine more mice were non-sensitized (i.p. saline) and used as control group (N/saline). After 5 weeks, anaphylaxis was induced with i.p. peanut extract and evaluated by the recognition of clinical symptoms and body temperature measurements. Specific IgG1, IgG2a, and IgE and cytokines were measured.

Results: Non-treated peanut-sensitized mice developed anaphylactic reactions following antigen challenge. Helminth crude extract-treated groups presented moderate symptoms. Nevertheless, P/AK-ES mice almost abolished the anaphylactic symptoms and impeded temperature drop after the challenge. All peanut-sensitized mice developed peanut-specific immunoglobulins. Helminth-treated groups showed an increase of specific IgG1 and IgG2a that peaked on weeks 3 and 4. By contrast, A. simplex E/S extract that hampered the production of specific IgE was observed in mice. Cytokines revealed a significant decrease in IL-5 and a significant increase in IL-10 and IFN-γ in the P/AK-ES group.

Conclusions: A. simplex E/S antigens have a potent and effective restraining effect on modulating peanut-induced anaphylaxis in mice.