Association of a NOD2 gene polymorphism and T-helper 17 cells with presumed ocular toxoplasmosis.

Retinochoroiditis manifests in patients infected with Toxoplasma gondii. Here, we assessed 30 sibships and 89 parent/case trios of presumed ocular toxoplasmosis (POT) to evaluate associations with polymorphisms in the NOD2 gene. Three haplotype-tagging single-nucleotide polymorphisms (tag-SNPs) within the NOD2 gene were genotyped. The family-based association test showed that the tag-SNP rs3135499 is associated with retinochoroiditis (P = .039). We then characterized the cellular immune response of 59 cases of POT and 4 cases of active ocular toxoplasmosis (AOT). We found no differences in levels of interferon γ (IFN-γ) and interleukin 2 produced by T-helper 1 cells when comparing patients with AOT or POT to asymptomatic individuals. Unexpectedly, we found an increased interleukin 17A (IL-17A) production in patients with POT or OAT. In patients with POT or AOT, the main cellular source of IL-17A was CD4(+)CD45RO(+)T-bet(-)IFN-γ(-) T-helper 17 cells. Altogether, our results suggest that NOD2 influences the production of IL-17A by CD4(+) T lymphocytes and might contribute to the development of ocular toxoplasmosis.

Rural electrification in Brazil and implications for schistosomiasis transmission: a preliminary study in a rural community in Minas Gerais State, Brazil.

OBJECTIVES: To evaluate the potential transmission of Schistosoma mansoni through well water pumped into households in a rural Brazilian community within the context of Brazil's rural electrification program Luz Para Todos (Light for All). METHODS: All households were interviewed about their water facilities and domestic water use, all household members were examined for S. mansoni infections and positives treated, and malacological and water contact studies were performed between 2001 and 2009. RESULTS: Thirty-one of the 142 households in the Virgem das Graças study area owned wells with electric pumps in 2009, vs. no wells in 2001, and the number of water storage tanks increased from 85 to 131. The potential for schistosomiasis transmission through piped well water was indicated by the recovery of Biomphalaria gabrata, including S. mansoni-infected snails, from wells, the presence of Biomphalaria in tanks and the ability of S. mansoni cercariae to remain infective for considerable distances in flowing water. However, access to well water was not associated with higher S. mansoni infection rates. CONCLUSIONS: Our results indicate that further studies are needed to determine the infectivity of well water and its impact on schistosomiasis transmission.

Effective anthelmintic therapy of residents living in endemic area of high prevalence for Hookworm and Schistosoma mansoni infections enhances the levels of allergy risk factor anti-Der p1 IgE.

In this work were investigated the relationship between Hookworm/Schistosoma mansoni infections and allergy related risk factors in two endemic areas with distinct prevalence of infections and co-infection. The intensity of infections, eosinophilia, allergy risk factors, infections status and anti-Der p1 IgE levels before and 2 years (population 1) and 3 years (population 2) after anthelmintic treatment, were evaluated. It was observed that the population with lower prevalence and intensity of infection (population 2) had lower eosinophils counts (>600/mm(3)) and higher animal contact than the population with higher parasites intensity (population 1). After anthelmintic treatment the intensity of S. mansoni single infection decreased, but no changes were observed in Hookworm and co-infected individuals. The anthelmintic treatment also enhanced anti-Der p1 IgE optical density in ELISA on the subgroups that became negative for helminth infection regardless of their previous infection condition in population 1. Facing that, we evaluated the anti-Der p1 IgE reactivity index, and the ratio (after/before treatment) was significantly higher in patients co-infected before treatment. On the other hand, no association between anti-Der p1 IgE reactivity index and the intensity of infections were observed. In conclusion, effective anthelmintic therapy of subjects from endemic areas with high prevalence of Hookworm and S. mansoni infections enhances anti-Der p1 IgE levels.