Cytokine profile in patients infected with Anisakis simplex in endemic areas: Dietary intervention with polyphenols: A working hypothesis

Anisakiasis is a zoonosis due to infection with the nematode Anisakis (A.) simplex. Humans represent an accidental host after ingesting raw fish infected with A. simplex. A. simplex larvae lead to a robust host immune response mostly at gastro-intestinal level and, usually, T helper (h)2 lymphocytes play a protective against this nematode. However, larvae can elude immunity triggering activation of T regulatory (Treg) cells, which, in turn, suppress Th2 responses via production of interleukin (IL)-10. According to our own experience in the area of Bari (south Italy) where anisakiasis is endemic, chronic urticaria (CU) is very often associated to A. simplex infection. The cytokine profile in CU patients with Anisakis infection is characterized by an elevated release of interferon-γ and IL-17, while IL-10 production is very low. This pattern of pro-inflammatory cytokine response was consistently detectable in patients who underwent a raw fish free diet regimen over a period of six months. In the light of the above considerations, we hypothesize that treating these patients with polyphenols it may be beneficial in terms of activation of Treg cell function. In fact, polyphenols have the capacity to expand Treg cell response in vitro. In this regard, activation of human Treg cells, by analogy to other helminthiasis, may lead to a reduction of allergic/inflammatory reaction in the course of human anisakiasis.