Project description:The lung schistosomulum of Schistosoma mansoni is a validated target of protective immunity elicited in vaccinated mice. To identify genes expressed at this stage we constructed a microarray, representing 3088 contigs and singlets, with cDNA derived from in vitro cultured larvae, and used it to screen RNA from seven life cycle stages. Clustering of genes by expression profile across the life cycle revealed a number of membrane, membrane-associated and secreted proteins up-regulated at the lung stage, that may represent potential immune targets. Two promising secreted molecules have homlogy to antigens with vaccine and/or immunomodulatory potential in other helminths.
Project description:Transcriptional profiling using two subsequent developmental stages of Schistosoma mansoni (Egg vs. Miracidium; Cercaria vs. 7-days-old Schistosomulum; 7-days-old Schistosomulum vs. Adult worms Two conditions experiment; Developmental Stage 1 vs. Developmental Stage 2
Project description:Transcriptional profiling using two subsequent developmental stages of Schistosoma mansoni (Egg vs. Miracidium; Cercaria vs. 7-days-old Schistosomulum; 7-days-old Schistosomulum vs. Adult worms
Project description:Schistosomiasis continues to be a significant public health problem1. Although vaccine development against this disease has experienced more failures than successes, encouraging results have recently been obtained using membrane-spanning protein antigens from the tegument of S. mansoni. Our group recently identified Sm29, an antigen that is predominantly recognized by IgG1 and IgG3 antibodies of resistant patients2. In the present study, we show that Sm29 is located on the surface of adult worms and lung-stage schistosomula. Immunization of mice with recombinant (r) Sm29 engendered 51% reduction in adult worm burdens, 60% reduction in intestinal eggs and 55% reduction in liver granulomas. Protective immunity in mice was associated with high titers of specific IgG1 and IgG2a and elevated production of IFN-γ, TNF-α and IL-12. Further, cellular responses of infected schistosomiasis patients to rSm29 consisted of elevated IFN-γ and an absence of IL-5. Gene expression analysis of worms recovered from rSm29 vaccinated mice relative to control mice revealed a significant (q< 0.01) down-regulation of 498 genes, while no up-regulation was detected. Among down-regulated genes, many of them encode surface antigens and proteins associated with immune signals suggesting that under immune attack schistosomes reduce the expression of critical surface proteins. This study demonstrates that the membrane-bound Sm29 protein is a new molecule that has great potential as a vaccine candidate against schistosomiasis. Keywords: Schistosoma mansoni gene expression in vaccinated mice
Project description:Schistosoma mansoni is a dioecious species, that is, it has two differentiated sexes. Interestingly, this sexual species evolved from a hermaphrodite ancestor. Indeed, most Platyhelminthes are hermaphrodites. Here we characterize the microRNAs of S. mansoni and quantify their differential expression between males and females.
Project description:High throughput sequencing of different life cycle stages of Schistosoma mansoni to identify loci that are methylated and use the information to focus on regions of biological relevance related to development and control of disease.