BACKGROUND:Penetration of skin, migration through tissues and establishment of long-lived intravascular partners require Schistosoma parasites to successfully manipulate definitive host defences. While previous studies of larval schistosomula have postulated a function for excreted/secreted (E/S) products in initiating these host-modulatory events, the role of extracellular vesicles (EVs) has yet to be considered. Here, using preparatory ultracentrifugation as well as methodologies to globally a ...[more]
Project description:Adult male and female Schistosoma mansoni worms were isolated from mice 7-weeks post-infection. Male material (Cy5) and female material (Cy3) were compared in a direct bimodal comparison. Five independent biological batches were used. Addtional dye-swap experiments male (Cy3) and female (Cy5) were performed using pooled samples of total RNA.
Project description:Background: Treatment and morbidity control of schistosomiasis relies on a single drug, praziquantel. Therefore, there is a pressing need to explore the effects of PZQ on the parasites at the molecular level and to pursue alternative and/or or synergistic drugs against schistosomiasis. Methodology: We used a custom-designed Schistosoma mansoni oligo-microarray to explore the effects of a sublethal dose of praziquantel on S. mansoni adult worms’ gene expression. We used functional analysis of gene interaction networks to identify differentially expressed genes that are known targets of other drugs already tested in humans for diverse disease conditions. Omeprazole, a proton pump inhibitor drug that is widely prescribed, was tested in combination with praziquantel. We comparatively assessed the efficacy of praziquantel or omeprazole alone and in combination against S. mansoni adult worms in vitro over a period of 120 hours. Principal Findings: We identified sets of genes that were affected by praziquantel on both paired and unpaired females, however with opposite gene expression patterns (up-regulated in paired and down-regulated in unpaired females), indicating that the transcriptomics changes induced by praziquantel are heavily influenced by the mating status. We also identified genes that were similarly affected by praziquantel in males and females. The use of sublethal doses of praziquantel together with omeprazole showed a significantly enhanced worm mortality in vitro compared to praziquantel alone, thus evidencing a synergic effect. Conclusions: Functional analysis of gene interaction networks is an important approach to identify genes whose expression is affected by one drug and that are at the same time known targets of other drugs already tested in humans for diverse disease conditions, thus pointing the latter as possible synergic drugs. Combined treatment with omeprazol increases the efficacy of praziquantel against S. mansoni adult worms in vitro, and additional in vivo studies are warranted. Two-condition experiment, PZQ-treated vs. untreated . Biological replicates: 2 with dye-swap
Project description:Although several markers have been associated with the characterization of regulatory T cells (Treg) and their function, no studies have investigated the dynamics of their phenotype during infection. Since the necessity of Treg to control immunopathology has been demonstrated, we used the chronic helminth infection model S. mansoni to address the impact on the Treg gene repertoire. Before gene expression profiling we first chose to study the localization and antigen-specific suppressive nature of classically defined Treg during infection. Presence of Foxp3+ cells were found especially in the periphery of granulomas and isolated CD4+CD25hiFoxp3+ Treg from infected mice blocked IFN-gamma and IL-10 cytokine secretion from infected CD4+CD25- effector T cells (Teff). Furthermore the gene expression patterns of Treg and Teff showed that in total 474 genes were significantly regulated during chronic schistosomiasis. Upon k-means clustering we identified genes exclusively regulated in all four populations including Foxp3, CD103, GITR, OX40 and CTLA-4: classical Treg markers. During infection however, several non-classical genes were up-regulated solely within the Treg population such as Slpi, Gzmb, Mt1, Fabp5, Nfil3, Socs2, Gpr177 and Klrg1. Using RT-PCR we confirmed aspects of the microarray data and in addition showed that the expression profile of Treg from S. mansoni-infected mice is simultaneously unique and comparative with Treg derived from other infections Regulatory T cells (Treg) or effector T cells (Teff) were FACS-sorted as CD4+CD25+ or CD4+CD25- from mesenteric lymph nodes (MLN) of naive mice or from mice infected with Schistosoma mansoni. Affymetrix MOE430A 2.0 genechips were used to identify genes differentially expressed in Treg or Teff under resting or infected conditions.
Project description:During its life cycle, the helminth parasite Schistosoma mansoni uses the freshwater snail Biomphalaria glabrata as an intermediate host to reproduce asexually generating cercariae for infection of the human definitive host. Following invasion of the snail, the parasite develops from a miracidium to a mother sporocyst and releases excretory secretory products (ESPs) that likely influence the outcome of host infection. To better understand molecular interactions between these ESPs and the host snail defence system, we determined gene expression profiles of haemocytes from S. mansoni resistant or -susceptible strains of B. glabrata exposed in vitro to S. mansoni ESPs (20ug/ml) for 1 h, using a 5K B. glabrata cDNA microarray.
Project description:In areas endemic for schistosomiasis, repeated exposure to infective cercariae is a frequent occurrence, and repeated exposure of murine skin to Schistosoma mansoni resulted in CD4+ T cells becoming hypo-responsive. Here potential contributory mechanisms were investigated. In the skin infection site, three mononuclear phagocyte populations were identified (tissue macrophages, dendritic cells, and macrophages) which exhibited up-regulation of genes associated with alternative activation, in particular the gene encoding RELMα. However, in repeatedly infected mice deficient in RELMα, there was no change in the abundance of mononuclear phagocytes in the skin, and CD4+ cells in the skin draining lymph nodes remained hypo-responsive. In mice deficient for IL-4Rα, required for alternative activation, levels of dermal regulatory IL-10 were reduced and there was an increase in the abundance of antigen presenting MHC-IIhigh cells, which was accompanied by increased numbers of CD4+ T cells. Although the absence of IL-4Rα did not translate into increased CD4+ cell responsiveness, they exhibited lower expression of Fas/FasL, resulting in decreased apoptosis/cell death and increased cell viability. This study highlights a mechanism through which IL-4Rα may regulate the immune system through the induction of IL-10 and regulation of Fas/FasL mediated cell death. Mice were infected 1x or 4x with S. mansoni cercariae via the pinnae. Pinnae were harvested 4 days after the final infection and the DEC obtained after an overnight culture in vitro. Cells were then stained with F4/80 APC and MHC-II PE and four different populations sorted (using the MoFlo or the Astrios) based on their expression profiles. Several mice (12-18) from each group were pooled to generate each replicate.