Serological screening of the Schistosoma mansoni adult worm proteome

BackgroundNew interventions tools are a priority for schistosomiasis control and elimination, as the disease is still highly prevalent. The identification of proteins associated with active infection and protective immune response may constitute the basis for the development of a successful vaccine and could also indicate new diagnostic candidates. In this context, post-genomic technologies have been progressing, resulting in a more rational discovery of new biomarkers of resistance and antigens for diagnosis.Methodology/Principal FindingsTwo-dimensional electrophoresed Schistosoma mansoni adult worm protein extracts were probed with pooled sera of infected and non-infected (naturally resistant) individuals from a S. mansoni endemic area. A total of 47 different immunoreactive proteins were identified by mass spectrometry. Although the different pooled sera shared most of the immunoreactive protein spots, nine protein spots reacted exclusively with the serum pool of infected individuals, which correspond to annexin, major egg antigen, troponin T, filamin, disulphide-isomerase ER-60 precursor, actin and reticulocalbin. One protein spot, corresponding to eukaryotic translation elongation factor, reacted exclusively with the pooled sera of non-infected individuals living in the endemic area. Western blotting of two selected recombinant proteins, major egg antigen and hemoglobinase, showed a similar recognition pattern of that of the native protein.Concluding/SignificanceUsing a serological proteome analysis, a group of antigens related to the different infection status of the endemic area residents was identified and may be related to susceptibility or resistance to infection

Cytokine profile, proliferation and phosphorylation of ERK1/2 and Akt in circulating mononuclear cells from individuals during the chronic intestinal phase of Schistosomiasis mansoni infection

Submitted by Nuzia Santos ([email protected]) on 2014-06-16T12:44:46Z No. of bitstreams: 1 Cytokine profile.pdf: 3149759 bytes, checksum: cf43916157d8279f1d5361396fd1143b (MD5)Made available in DSpace on 2014-06-16T12:44:46Z (GMT). No. of bitstreams: 1 Cytokine profile.pdf: 3149759 bytes, checksum: cf43916157d8279f1d5361396fd1143b (MD5) Previous issue date: 2012Fundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brazil/Universidade Federal de Minas Gerais. Escola de Enfermagem. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais.Escola de Enfermagem. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Brasilia, DF, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, BrazilUniversidade Federal de Minas Gerais. Faculdade de Medicina. Departamento de Clínica Médica, Cirurgia. Belo Horizonte, MG, Brazil/Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais. Belo Horizonte, BrazilFundação Oswaldo Cruz. Centro de Pesquisas René Rachou. Belo Horizonte, MG, Brazil/Instituto Nacional de Ciência e Tecnologia em Doenças Tropicais. Belo Horizonte, BrazilUniversidade Federal de Minas Gerais. Faculdade de Medicina. Departamento de Cirurgia. Belo Horizonte, MG, BrazilBackground :The immune response to Schistosoma mansoni is characterized by a granulomatous reaction around the parasite eggs that are trapped in the host liver, and this reaction modulates the immune response during the chronic phase of the disease. The typical peripheral blood mononuclear cell (PBMC) response of patients during the chronic intestinal phase of infection is characterized by a decreased response to an S. mansoni soluble egg antigen. To obtain a greater understanding of Schistosoma infections, this study investigated the effects of the soluble egg antigen (SEA) and soluble adult worm antigen (SWAP) of S. mansoni on cellular proliferation, cytokine production, and ERK1/2 and Akt phosphorylation in PBMCs from infected (XTO) and egg-negative (NI) individuals living in the same endemic area. Methods : The activation status was evaluated by cell immunophenotypic staining (cytometry). The cell proliferation assay was by CFSE method. Cytokine detection assay (Th1 and Th2) was by Cytometric Bead and Array phosphorylation status was by ELISA. Results : The XTO, NI and BD (blood donor) individuals from an area not endemic for schistosomiasis were compared. The CD4+ T lymphocyte proliferation rate was lower in the XTO group, but not the NI group, after SEA stimulation compared to the BD group. The CD8+ T cell proliferation rate was lower in the XTO group in the unstimulated cultures and after both SEA and SWAP stimulation compared to the BD group. Cytokine analysis after either SEA or SWAP stimulation showed a balanced cytokine pattern in the XTO and NI groups. ERK1/2 and Akt phosphorylation were only marginally detected in all groups; however, a decrease in ERK 1/2 phosphorylation was observed in the SWAP-stimulated XTO group compared to both the NI and BD groups. Conclusions : The data indicate that SEA-stimulated CD4+ T cells from infected patients have a lower proliferation rate than the same cells from the NI group. Furthermore, we observed that SWAP stimulation influences ERK1/2 phosphorylation in the XTO group

Genetic Epidemiology of Fecal Egg Excretion During Schistosoma mansoni Infection in an Endemic Area in Minas Gerais, Brazil

There is considerable variation in the level of fecal egg excretion during Schistosoma mansoni   infections. Within a single endemic area, the distribution of egg counts is typically overdispersed, with the majority of eggs excreted coming from a minority of residents. The purpose of this study was to quantify the influence of genetic factors on patterns of fecal egg excretion in a rural study sample in Brazil. Individual fecal egg excretions, expressed in eggs per gram of feces, were determined by the Kato-Katz method on stool samples collected on three different days. Detailed genealogic information was gathered at the time of sampling, which allowed assignment of 461 individuals to 14 pedigrees containing between 3 and 422 individuals. Using a maximum likelihood variance decomposition approach, we performed quantitative genetic analyses to determine if genetic factors could partially account for the observed pattern of fecal egg excretion. The quantitative genetic analysis indicated that between 21-37% of the variation in S. mansoni egg counts was attributable to additive genetic factors and that shared environment, as assessed by common household, accounted for a further 12-21% of the observed variation. A maximum likelihood heritability (h2) estimate of 0.44 ± 0.14 (mean ± SE) was found for the 9,604 second- and higher-degree pairwise relationships in the study sample, which is consistent with the upper limit (37%) of the genetic factor determined in the variance decomposition analysis. These analyses point to the significant influence of additive host genes on the pattern of S. mansoni fecal egg excretion in this endemic area