TRICHINELLA SPIRALIS INFECTION PROTECTS AGAINST OVALBUMININDUCED ALLERGIC BRONCHIAL ASTHMA IN A MURINE MODEL

Abstract

Allergic bronchial asthma is a long-lasting illness of the respiratory system characterized bychronic inflammation of the respiratory airways with abnormal Th2-type immune responses tospecific allergens. The accumulation of scientific evidence supports the beneficial effects ofsome parasitic infections in animal models of allergic diseases. Thus, the aim of this work wasto discover the influence of infection with T. spiralis on ovalbumin-induced acute allergic airwayinflammation in mice and to investigate whether this effect is correlated to the infectiondose or not. Therefore, the severity of respiratory airways inflammation, the leukocyte counts inthe blood and BALF, immunohistochemistry of FOXP3+CD4+T cells and the levels of IL-6, IL-13, and IL-10 were assessed. In this experiment, 120 male laboratory bred mice were randomlydivided into six groups: induced asthma, saline control, low dose preventive, high dose preventive,low dose therapeutic and high dose therapeutic groups. T. spiralis infection attenuated theintensity of pulmonary inflammation, decreased numbers of eosinophils in BALF and blood,reduced levels of IL-6 and IL-13 and elevated levels of IL-10 with a significant upregulation ofFOXP3+CD4+T cells expression compared to the uninfected induced asthma group. The preventivegroups showed the best results with no significant difference between effects of the low andthe high doses. In conclusion, T. spiralis infection reduced Th2 type infammation and augmentedregulatory immune response in ovalbumin-induced acute allergic airway inflammation withbetter preventive than therapeutic effects. Further investigations are needed to determine theminimal dose of infection that gives the best influence.