Immunopathological changes in schistosomiasis and pulmonary tuberculosis: an approach towards an effective immunotherapy

Schistosomiasis and pulmonary tuberculosis [T.B.] are diseases that have a special importance in the developing world. Information derived from experimental models suggested that a number of cytokines released from Th-I and Th-2 cells play a role in granuloma formation in such diseases. Yet, it had not revealed a common underlying mechanism in order to compare the immunopathological events in a systematic manner. Although both schistosomiasis and T.B. can be acquired due to living under unhygienic conditions, we seldom meet cases of active or patent mixed schistosomiasis and T.B. in our clinical work. This motivated us to study the immunopathogenesis of inflammatory responses in these two diseases. 45 patients and 15 healthy controls constituted the material of this study. Patients were divided into 3 groups, each one included 15 patients: group I:pure schistosomal cases, group II:pure T.B. patients and group III: mixed T.B. and schistosomiasis. Beside routine laboratory investigations for diagnosis of schistosomiasis and T.B.,the following cytokines were estimated: IL-2, TNF-alpha, IFN-gamma, IL-4, IL-5, IL-6, and IL-10. Our results revealed that in pure schistosomal patients, Th-2 cytokines were significantly dominated which reflect a major role of these cytokines in humoral immunity. In the near future, this finding may allow the use of anti-idiotype antibodies as a therapeutic option in schistosomiasis. On the other hand, in pure T.B. patients Th-1 cytokines were statistically increased which may indicate the major role of hyperactive state of cellular immunity. Hence, this approach may allow therapeutic interventions to target critical cytokines to be used as a tool in the concerned disease process

Phagocytic activity of neutrophils in human fascioliasis before and after treatment

Neutrophil phagocytic function was studied in 15 patients with chronic fasciolosis and 5 in the incubating phase of the disease. The results were compared with a control group. The chemotactic index, which is the ratio of directed to non-directed migration, the NBT reduction test, which estimated phagocytosis, and the more recent and specific test, the chemiluminescence, which measured phagocytosis, and intracellular killing were performed. The results showed that in fascioliasis chemotactic activity, NBT and chemiluminescence index were significantly increased as compared with control. This increase was more prominent in the acute phase. In this stage, the immature parasites are in close contact with the liver tissue. With chronicity of infection, they reach the bile ducts and inflammation in the liver parenchyma subsides. At this stage, a lower level of metabolites and antigens reach the tissue, while the majority pass with bile to the intestinal lumen. The indices returned to normal level after treatment of fascioliasis. This signifies disappearance of all stimuli responsible for activation of PMV phagocytes