Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recent studies indicate that egg granuloma formation in murine Schistosoma mansoni infection is associated with Th2-mediated immune responses. The present study was designed to analyze dynamically the Th1 and Th2 responses in S. japonicum-infected animals and compare them with the results seen with S. mansoni. C3H mice were infected with 10 to 20 cercariae of S. japonicum and sacrificed 3 to 22 weeks later. Spleen cells were stimulated with parasite antigens (egg and adult worm) or the mitogen concanavalin A. Interleukin-2 (IL-2), IL-4, IL-5, and gamma interferon (IFN-gamma) levels were measured in the culture supernatants by enzyme-linked immunosorbent assay (ELISA) or bioassays. Additionally, cytokine-producing cells were enumerated by ELISPOT. The results show that Th2 cytokine production, characterized by IL-4 and IL-5, represents the major response in the first month after egg laying begins, while the Th1 functions of IFN-gamma and IL-2 production are greatly depressed. However, by 22 weeks Th2 responses have diminished and IFN-gamma production in response to concanavalin A is apparent. IL-2 responses are minimal at all times. In vitro depletion of T-cell subsets indicates that CD4+ cells are the major subset responsible for production of IL-5 at 7 weeks of infection. These findings suggest that, as in the case of S. mansoni infection, S. japonicum-induced immunopathology is temporally associated with the host Th2 response, although other experiments indicate that IFN-gamma is also involved.
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PMID:Dynamic analysis of splenic Th1 and Th2 lymphocyte functions in mice infected with Schistosoma japonicum. 167 41

Three study groups in the Rusizi plain (Burundi) were examined parasitologically (duplicate 28 mg Kato slides) and clinically (history, abdominal palpation) 0, 1.5, 3, 6, 12 and 24 months after treatment for Schistosoma mansoni infection. Infected subjects in Maramvya (n = 430) were treated randomly with oxamniquine 20, 30 or 40 mg/kg; those in Bulinga (n = 457) with praziquantel, 20, 30 or 40 mg/kg; those in Bulamata (n = 333) with praziquantel, 30 or 40 mg/kg. In children (less than 20 years) in Maramvya and Bulamata, infection rates and intensities returned almost to pretreatment levels one to 2 years after treatment. In Bulinga, reinfection in children was much less intense. Hardly any reinfection occurred in adults in Bulinga and Maramvya; in Bulamata, half of the cured adults were reinfected, most of them lightly, 2 years after treatment. The initial parasitological advantage of the higher dosages of both drugs disappeared generally 3-12 months after treatment. There was no indication of predisposition to heavy reinfection after treatment of subjects with initial high egg counts. Little relation between pre-treatment egg count and morbidity was observed. The impact of chemotherapy on hepatomegaly was limited and observed only in adults treated with 40 mg/kg of either drug. Spleen rates in children and adults were not affected. Abdominal pain was reduced in almost all treatment groups for 3 to 24 months. The frequency of bloody diarrhoea decreased dramatically in children and adults from all 3 villages. This effect lasted 24 months in Maramvya, 12 months in Bulinga and 6 months in Bulamata, and was not dose-dependent. It is concluded that: (i) repeated population chemotherapy combined with sanitation is necessary to achieve lasting impact on infection rates; (ii) retreatment intervals should be adapted to age group and, possibly, local endemicity levels; (iii) the morbidity impact of population chemotherapy in these conditions was greater on intestinal than on hepatosplenic disease; (iv) lower, cheaper treatment schedules may in the long term be as effective as those with high cure rates.
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PMID:Two-year follow-up of Schistosoma mansoni infection and morbidity after treatment with different regimens of oxamniquine and praziquantel. 251 74

Splenic suppressor cell activity was evaluated in 10 patients with advanced hepatosplenic Schistosomiasis mansoni undergoing elective splenectomy. We used cell mixing experiments to assess the effect of mitomycin-C-treated spleen cells on antigen and mitogen-induced 3H-thymidine incorporation of responder cells. The suppressor to responder ratio was 1.0. Spleen cells from 7 of 10 patients caused at least 20% suppression of phytohemagglutinin-induced 3H-thymidine incorporation of one or more populations of responder cells (spleen cells, autologous and allogeneic peripheral blood mononuclear cells)Responses of peripheral blood mononuclear cells to streptokinase-streptodornase and schistosome soluble egg and worm antigen preparations also were inhibited by co-cultured spleen cells. An inverse correlation was apparent between the spleen cell response to PHA and the suppressor activity of that spleen cell population (r = -0.74, p less than 0.05). Cell purification procedures showed that the active suppressor splenic cell was non-adherent and rosetted neuraminidase-treated sheep erythrocytes. This splenic suppressor T lymphocyte may modulate splenic and peripheral blood lymphocyte responses in patients with hepatosplenic schistosomiasis.
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PMID:Suppression splenic T lymphocytes in human hepatosplenic Schistosomiasis mansoni. 696 56

Peri-portal fibrosis can be a serious sequelae of Schistosoma mansoni infection. Age or duration of exposure have been identified as important risk factors, but their relative importance cannot be easily separated. Here, we have compared two cohorts, aged 6-50 years and resident for ten years or since birth, from two neighbouring villages (Booma and Bugoigo) on the eastern shore of Lake Albert, Uganda. Parasitological measurements were similar, whereas the prevalence of peri-portal fibrosis was 5-fold higher in Booma. Data from the cohorts were pooled to assess the relative contribution of age and duration of residency on the risk of disease. Amongst adults, duration of residency was the critical risk factor--individuals aged 17-31 years resident for more 22 years had an almost 12-fold increased risk of fibrosis than those resident for less than 15 years. Height-standardised Splenic Vein Diameter (SVD), Portal Vein Diameter (PVD), Para-sternal Liver Length (PLL) and Spleen Length (SL) values were all higher in Booma, and each organometric parameter except PLL increased with the severity of fibrosis. Our results clearly demonstrate that duration of exposure is a critical risk factor for the development of peri-portal fibrosis and its sequelae in adults. This parameter should therefore be a routine measurement during epidemiological surveys of S. mansoni.
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PMID:Hepatosplenic morbidity in two neighbouring communities in Uganda with high levels of Schistosoma mansoni infection but very different durations of residence. 1496 13