BACKGROUND: The study conclusively demonstrated that () neutrophil-activating protein (HP-NAP) has the ability to switch a pro-allergic Th2 response to a Th1 response. Furthermore, it investigated the effects of HP-NAP on TH1 and TH2 cytokines, as well as airway inflammation in a rat model of allergic asthma, and compared these effects with those of . MATERIALS AND METHODS: and HP-NAP were prepared based on a previous study. Sixty male Blab/c mice were used for histopathological and immunological studies, divided into six groups of 10. Five mice from each group were selected for histopathological studies, and five were selected for measuring changes in TH cytokine levels and eosinophil count. The study was conducted over 31 days. RESULTS: Histological staining was performed on six selected groups. After treatment with HP-NAP, the recipient treatment group demonstrated a significant decrease in interleukin (IL)-4, IL-5, and total immunoglobulin E (IgE) levels, along with a significant increase in IL-2 and interferon-gamma (IFN-γ) levels. Furthermore, the number of eosinophils in the bronchoalveolar lavage fluid (BALF) of mice treated with HP-NAP significantly decreased compared to the positive control samples. CONCLUSION: Our research findings conclude that HP-NAP can significantly reduce serum levels of IgE, IL-5, and IL-4, while increasing levels of IL-2 and IFN-γ, compared to . HP-NAP can be a useful therapeutic agent for preventing and treating allergic asthma.