Cytokine production in Hymenolepis nana infection.

BACKGROUND Although many experimental studies provide convincing evidence that type II immunity is protective against helminths, recent data in mice demonstrate that Th1 is also important in some cestodes like Hymenolepis nana. OBJECTIVES To identify the role of Th1 and Th2 lymphocytes in immunity against H. nana, the levels of IL-12, IFNgamma, IL-5, and IL-13 were determined in serum of humans infected with this cestode. METHODS A total of 31 patients (case) with H. nana infection and 30 clinically healthy individuals (control) was included in this study. Measurements of IL-12, IFNgamma, IL-13 and IL-5 in serum samples were performed by solid-phase sandwich enzyme linked immunosorbant assay. Differential leukocyte count was also done. T test, Mann Whitney U test and Wilcoxan W test were used for data analysis. RESULTS The mean concentrations of IFNgamma, IL-12 and IL-5 in the sera of patients with H. nana infection were higher than the control group, but only the differences between the concentrations of IFNgamma (P<0.001) and IL-13 (P<0.05) in the two groups were significant. There was an increase in the percentage of monocytes, eosinophils and lymphocytes in patients when compared to the controls, but this increase was not significant. CONCLUSIONS Results from the present study in humans are in agreement with experimental studies in animals in which both Th1 and Th2 responses occur in H. nana infection.