STUDIES ON SOME CYTOKINES IN SERUM OF HUMAN INFECTED WITH SCHISTOSOMA MANSONI
Soad M. Yousef1, Mohammed H. Hegab1, Mohammed N. El Khashab2, Dalia A. Abo El-Maaty1, Rania S. Hamza1, Tahani I. Farag1
Departments of Medical Parasitology1 and Tropical Medicine2, Faculty of Medicine, Zagazig University, Egypt.
Background: The cytokine network in schistosomiasis plays an important role in coordination responses of the innate system cells and most of them are involved in the regulation of inflammatory and immunologic responses in pathologic and physiologic conditions. An imbalance of cytokines production may be related to disease progression. Objective: To evaluate the levels of cytokines (IFN- γ, IL-4, IL-10 and IL-13) in serum from Schistosoma mansoni infected individuals and study their relations to the degree of periportal fibrosis (PPF) and intensity of infection. Methodology: Fifty patients with schistosomiasis mansoni were involved in the study. For all patients, clinical histories, quantitative egg counts and ultrasound classification were done. Control group comprised twenty individuals being negative for Schistosoma and free from other parasites. The levels of four human cytokines (IFN-γ, IL-4, IL-10 and IL-13) were determined in schistosomiasis patients and control group using enzyme-linked immunosorbent assay. Results: Men represented 73.3٪ of patients with severe degree of fibrosis with significant increase in their age compared to other degrees and 100٪ of these patients had a history of frequent water contact. Significantly higher levels of IFN-γ and IL-4 were detected in Gd0 and GdI compared to the control group, while IL-10 level significantly increased in patients of Gd0, GdI and GdII and highly significantly decreased in patients with GdIII compared to the control group. Regarding IL-13, it showed a highly significant increase in different grades of fibrosis when compared to control group. The ultrasonographic score of PPF showed positive correlation with the the level of IL-13, while it showed an inverse correlation with the levels of IFN-γ, IL-4 and IL-10 in serum of patients. In relation to the intensity of infection, it showed a positive correlation with the levels of IL-10, IFN-γ and IL-4, but a negative correlation with IL-13 level in serum of patients. Conclusion: Schistosomiasis appears to induce an increase in serum level of IL-4 and IL-10 but low level of IL-13 in early grades of fibrosis for down-modulating immunopathological responses. Also, production of high level of IFN-γ early in the disease suggesting that IFN-γ plays a role in the regulation of fibroblast activity. While with moderate to severe fibrosis, low levels of IFN-γ, IL-4 and IL-10 with a high level of IL-13 indicating that IL-13 is the main cytokine involved in the development of hepatic fibrosis.
June 2012