CELLULAR IMMUNE RESPONSE IN CHRONIC SCHISTOSOMIASIS HAEMATOBIUM

Abstract

The immune response to Schistosoma haematobium infection has diverse effects on the host-parasite relationship . One aspect is protective and may minimize the acquisition of new worms . The other aspect is pathological. and may contribute to morbidity by increasing the granulomatous reaction. In this study, the immune response in human infections, have been investigated with intentions to investigate the immune response in relation different pathological features of the disease, and extend the knowledge to the regulatory cytokines . The study was performed in two phases . The first phase, a total of 129 patients were subjected to clinical, parasitological and cellular immune response investigations, and recieived antibilharzial chemotherapy ( praziquantel 40 mg/ Kg body weight) . The second phase of the study was done by following up for clinical , parasitological or cellular immune response changes after one month (63 patients), three months (28 patients) and six months (13 patients) after receiving the therapy . The cellular immune response investigations included PBMN prolifeative response and in Yi1ro. cytokine production and assay. Our ieuslts are summarized in the following points : 1) The immune response is down-modulated in chronic schistosomiasis, and a causal relationship between the parasitic load and the impairment of the immune functions are suggested 2) The down-modulation of immune response associated with chronic schistosomiasis, is correlated to the intensity of infection as indicated by egg count . This observation points to the role of schistosoma) egg antigens in the impairment of immune response. 3) The down-modulation of immune response is correlated with the eosinophil count . This relation mostly not due to suppressive effect of eosinophils themselves, as the resistance to treatment is inversely correlated with• eosinophil count . However, their levels may reflect variation in other immunological processes more directly involved in the pathogenesis of immune response downmodulation .