Interleukin-4, immunoglobulin E and immunoglobulin A and resistance to re-infection with Schistosoma haematobium before and after chemotherapy.

The role of serum IL-4, IgE and IgA in protective immunity had been determined in 88- S. haematobium infected-individuals before and 3, 6, 9 and 12 months after treatment with a single dose of praziquantel. Before treatment, IL-4 level was found to be highly significant in all stages of infection, there was a positive correlation between IL-4 levels and egg count. Whereas serum IgE and IgA levels were significantly high in late infected group showing a negative correlation with egg count. After praziquantel treatment, IL-4 levels decreased gradually while IgE and IgA levels were significantly increased in all patients. At 9 and 12 months, viable ova were detected in 11 cases (12.5%), they were re-infected after treatment showing an increase in IL-4 levels, and a decrease in both serum IgE and IgA. These results indicate that IL-4 plays an important role in suppression of severe inflammatory responses associate with persistence of the parasitic stages. Also, serum IgE and IgA participate in protective immunity against S. haematobium infection. It may be essential to administer a second dose of praziquantel to all persons living in endemic areas who are likely to be in contact with infested water.

Detection of cellular and humoral markers (IL-2, IFN-gamma and IgE) in sera of patients with urinary schistosomiasis.

Schistosomiasis continues to be major health problem throughout the developing world. Infection with Schistosoma haematobium is associated with very high morbidity. The work aimed at the determination of role of cellular immune response (IL-2, and IFN-gamma) and specific humoral IgE in protective immunity in human urinary schistosomiasis, as a function of both age and infection intensity including examination of changes in immunoresponsiveness following curative therapy. The study revealed that IL-2,IFN-gamma level were higher in all patients compared to the normal control group and the levels were higher in lightly infected groups than heavily infected ones with no respect to age. IgE levels showed higher values compared to normal individuals and IgE levels were higher in children groups than in adults regardless of the intensity of infection. IL-2, IFN-gamma and IgE levels were higher in patients with mixed S. mansoni and S. haematobium infections than monoinfected patients. Follow up of patients 2 months, 4 months and 12 months after Praziquantel treatment showed that the level of IL-2 and IgE fell back to normal values after 4 months while IFN-gamma remained high, IL-2, IFN-gamma and IgE were raised once more after 12 months.