Background and Aim: Anisakis is a global challenge for a fish product which may lead to a decrease in economic value and consumers' preference. Skipjack (Katsuwonus pelamis) in Kupang, Nusa Tenggara Timur, Indonesia, have important economic value for local fisheries. Anisakis typica is one of the Anisakis species which potent to induce an allergic reaction. However, the study about A. typica involved in the dendritic cells (DCs), T helper 1 (Th₁), T helper 2 (Th₂), and regulatory T cells (Tregs) is still limited. This study aimed to analyze the dynamic changed of the immune system including DCs, CD4⁺ T cells, and Tregs after 1 week of A. typica sensitization.

Materials and Methods: Twenty-four male Balb/C mice were randomly divided into four groups (n=6), mice treated with crude A. typica extract (CAE) 50, 75, and 100 mg/kg BW, respectively. CAE was given orally per day for a week. At the end of the experiment, the animals were sacrificed and the spleen was collected. DCs were labeled as CD11c⁺ interleukin-6⁺ (IL-6⁺); CD4⁺ T cells were distinguished as Th¹ (CD4⁺ interferon-γ⁺ [IFN-γ⁺]) and Th² (CD4⁺ IL-4⁺ and CD4⁺ IL-5⁺); Tregs were labeled as CD4⁺CD25⁺CD62L⁺. The expression of each cell was determined by flow cytometry.

Results: Our result described that CAE elicits CD11c⁺ IL-6⁺, CD4⁺ IFN-γ⁺, CD4⁺ IL-4₊, and CD4₊ IL-5₊ and reduces CD4₊CD25₊CD62L₊ significantly (p<0.05) in dose-dependent manner in mice after A. typica infection.

Conclusion: The Th₁/Th₂ ratio after A. typica crude extract treatment exhibits a mixed pattern rather than the classical model allergy to food antigens. Our study is expected as a basic understanding of the changes in immune response after A. typica infection.

Keywords: allergy, dendritic cells, inflammation, nematode, regulatory T cells.