333 research outputs found
Helminth parasite proteomics: from experimental models to human infections
Schistosomiasis is a major human helminth infection endemic in developing countries. Urogenital schistosomiasis, caused by S. haematobium, is the most prevalent human schistosome disease in sub-Saharan Africa. Currently control of schistosome infection is by treatment of infected people with the anthelmintic drug praziquantel, but there are calls for continued efforts to develop a vaccine against the parasites. In order for successful vaccine development, it is necessary to understand the biology and molecular characteristics of the parasite. Ultimately, there is need to understand the nature and dynamics of the relationship between the parasite and the natural host. Thus, my studies have focused on molecular characterization of different parasite stages and integrating this information with quantitative approaches to investigate the nature and development of protective immunity against schistosomes in humans. Proteomics has proved a powerful tool in these studies allowing the proteins expressed by the parasite to be characterized at a molecular and immunological level. In this review, the application of proteomic approaches to understanding the human-schistosome relationship as well as testing specific hypotheses on the nature and development of schistosome-specific immune responses is discussed. The contribution of these approaches to informing schistosome vaccine development is highlighted
TNFα-stimulated gene-6 (TSG6) activates macrophage phenotype transition to prevent inflammatory lung injury
TNFα-stimulated gene-6 (TSG6), a 30-kDa protein generated by activated
macrophages, modulates inflammation; however, its mechanism
of action and role in the activation of macrophages are not fully understood.
Here we observed markedly augmented LPS-induced inflammatory
lung injury and mortality in TSG6−/− mice compared with WT
(TSG6+/+) mice. Treatment of mice with intratracheal instillation of
TSG6 prevented LPS-induced lung injury and neutrophil sequestration,
and increased survival in mice. We found that TSG6 inhibited the
association of TLR4withMyD88, thereby suppressing NF-κB activation.
TSG6 also prevented the expression of proinflammatory proteins (iNOS,
IL-6, TNFα, IL-1β, and CXCL1) while increasing the expression of antiinflammatory
proteins (CD206, Chi3l3, IL-4, and IL-10) in macrophages.
This shift was associated with suppressed activation of proinflammatory
transcription factors STAT1 and STAT3. In addition, we observed
that LPS itself up-regulated the expression of TSG6 in TSG6+/+
mice, suggesting an autocrine role for TSG6 in transitioning macrophages.
Thus, TSG6 functions by converting macrophages from a
proinflammatory to an anti-inflammatory phenotype secondary to
suppression of TLR4/NF-κB signaling and STAT1 and STAT3 activation
Gr1+IL-4-producing innate cells are induced in response to Th2 stimuli and suppress Th1-dependent antibody responses
Alum is used as a vaccine adjuvant and induces T<sub>h</sub>2 responses and T<sub>h</sub>2-driven antibody isotype production against co-injected antigens. Alum also promotes the appearance in the spleen of Gr1+IL-4+ innate cells that, via IL-4 production, induce MHC II-mediated signaling in B cells. To investigate whether these Gr1+ cells accumulate in the spleen in response to other T<sub>h</sub>2-inducing stimuli and to understand some of their functions, the effects of injection of alum and eggs from the helminth, Schistosoma mansoni, were compared. Like alum, schistosome eggs induced the appearance of Gr1+IL-4+ cells in spleen and promoted MHC II-mediated signaling in B cells. Unlike alum, however, schistosome eggs did not promote CD4 T cell responses against co-injected antigens, suggesting that the effects of alum or schistosome eggs on splenic B cells cannot by themselves explain the T cell adjuvant properties of alum. Accordingly, depletion of IL-4 or Gr1+ cells in alum-injected mice had no effect on the ability of alum to improve expansion of primary CD4 T cells. However, Gr1+ cells and IL-4 played some role in the effects of alum, since depletion of either resulted in antibody responses to antigen that included not only the normal T<sub>h</sub>2-driven isotypes, like IgG1, but also a T<sub>h</sub>1-driven isotype, IgG2c. These data suggest that alum affects the immune response in at least two ways: one, independent of Gr1+ cells and IL-4, that promotes CD4 T cell proliferation and another, via Gr1+IL-4+ cells, that participates in the polarization of the response
t(11;17)(p15;q21) NUP98/?
Review on t(11;17)(p15;q21) NUP98/?, with data on clinics, and the genes involved
T Regulatory Cell Responses to Immunization with a Soluble Egg Antigen in Schistosoma mansoni-Infected Mice
The aim of the study is to characterize the phenotypes of CD4+ CD25+ T regulatory cells within the liver granulomas and association with both Foxp-3 gene expression and splenic cytokines. Naïve C57BL/6 mice were intravenously injected with multiple doses of the soluble egg antigen (SEA) 7 days before cercarial infection. The immunized and infected control groups were sacrificed 8 and 16 weeks post-infection (PI). Histopathology, parasitological parameters, splenic phenotypes for T regulatory cells, the FOXP-3 expression in hepatic granuloma using real-time PCR, and the associated splenic cytokines were studied. Histopathological examination of the liver revealed remarkable increase in degenerated ova within hepatic granuloma which decreased in diameter at weeks 8 and 16 PI (P<0.01). The percentage of T regulatory cells (CD4+ CD25+) increased significantly (P<0.01) in the immunized group compared to the infected control at weeks 8 and 16 PI. The FOXP-3 expression in hepatic granulomas increased from 10 at week 8 to 30 fold at week 16 PI in the infected control group. However, its expression in the immunized group showed an increase from 30 at week 8 to 70 fold at week 16 PI. The splenic cytokine levels of pro-inflammatory cytokines, IFN-γ, IL-4, and TNF-α, showed significant decreases (P<0.05) compared to the infected control group. In conclusion, the magnitude and phenotype of the egg-induced effects on T helper responses were found to be controlled by a parallel response within the T regulatory population which provides protection in worm parasite-induced immunopathology
Development of a vaccine strategy against human and bovine schistosomiasis: background and update
Ocena pobrania z dietą wybranych składników mineralnych przez młodzież w wieku 13-15 lat w zależności od płci oraz miejsca zamieszkania
Absorption of minerals compound by the investigated population aged 13-15 depending on gender and place of residenceIntroduction.The life period between 11-19 years of age is defined as the adolescence (phase), which is a period of intense growth and development, during which the organism ultimately heads for achieving a biological, psychological and social maturity. During this period, proper nutrition is an essential factor in the harmonious development of the young organism and to achieve a high health potential.The aim.The aim of this study was to evaluate the absorption of minerals compound by the investigated population depending on gender and place of residence.Material and methods.The evaluation was performed by 24 hours diet recall in randomly selected schools in Krakow and Skawina area. The content of mineral compounds (Na, K, Ca, P, Mg, Fe, Zn, Cu) consumed by the subjects was assessed by the use of the "Dieta 2.0" software.Results. It were discovered a numerous irregularities in consumption of selected minerals, including significant calcium deficiency, and also the excess of sodium in the diet. Calcium deficiency combined the excess of phosphorus can adversely affect the achievement of the peak bone mass and increase the risk of osteoporosis in later stages of life. Also demonstrated high sodium and low potassium intakes could contribute to the development of cardiovascular disease
Evaluation of Wuchereria bancrofti GST as a Vaccine Candidate for Lymphatic Filariasis
Lymphatic parasites survive for years in a complex immune environment by adopting various strategies of immune modulation, which includes counteracting the oxidative free radical damage caused by the host. We now know that the filarial parasites secrete antioxidant enzymes. Among these, the glutathione-S-transferases (GSTs) have the potent ability to effectively neutralize cytotoxic products arising from reactive oxygen species (ROS) that attack cell membranes. Thus, GSTs have the potential to protect the parasite against host oxidative stress. GSTs of several helminthes, including schistosomes, fasciola and the filarial parasite Seteria cervi, are also involved in inducing protective immunity in the host. The schistosome 28 kDa GST has been successfully developed into a vaccine and is currently in Phase II clinical trials. Thus, GST appears to be a potential target for vaccine development. Therefore, in the present study, we cloned W. bancrofti GST, and expressed and purified the recombinant protein. Immunization and challenge experiments showed that 61% of protection could be achieved against B. malayi infections in a jird model. In vitro studies confirm that the anti-WbGST antibodies participate in the killing of B. malayi L3 through an ADCC mechanism and enzymatic activity of WbGST appears to be critical for this larvicidal function
Cross-regulatory role of interferon-gamma (IFN-Γ), IL-4 and IL-10 in schistosome egg granuloma formation: in vivo regulation of Th activity and inflammation
This study examined the relationship ofIL-4, IL-10 and IFN-Γ with regard to the local granuloma (GR) and draining lymph node (LN) response to Schistosoma mansoni eggs. Synchronized GR were induced in naive and schistosome-infected mice at the vigorous (8 weeks) and late chronic (20 weeks) stages. In LN cultures, IL-10 and IFN production peaked on day 4 and was greatest for 8 week-infected mice. All GR cultures contained IFN, but compared with naive mice IL-10 production was accelerated at 8 weeks and abrogated at 20 weeks, consistent with expansion and abatement of Th2 activity, Cytokine neutralization was performed in egg-challenged, naive mice that were adoptively sensitized with lymphoid cells from 8 week-infected donors. GR size, GR macrophage tumour necrosis factor (TNF) production and egg antigen-elicited IL-2, IL-4, IL-5, IL-10 and IFN were examined on day 4 of GR formation, Anti-IFN augmented GR area by 40%, increased local IL-4 and IL-10, but decreased IFN and TNF production. In corresponding LN cultures, IFN decreased by about 50%, while IL-2, IL-4, IL-IO and lL-5 increased by nearly two-, four-, five- and six-fold, respectively, Anti-IL-10 did not affect GR size or GR cytokines, but increased IFN levels in LN cultures four-fold and decreased IL-2, IL-4, lL-5 and IL-10. Anti-IL-4 abrogated GR area by 40%, along with a reduction in local IL-4 and TNF production. In LN, IL-4 depletion reduced IL-4 and IL-5 by 60–70% and increased IFN levels. These results support the notion of a cross-regulatory network in which IFN inhibits Th2 and IL-10 inhibits ThI cells. IL-4 fosters Th2 cell differentiation in LN, but also performs a critical recruitment function in the eosinophil-rich schistosome egg-induced GR, whereas IFN contributes to enhanced GR macrophage function.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/73324/1/j.1365-2249.1994.tb05503.x.pd
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