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Schistosomiasis mansoni is a serious problem of public health in the world and the improvement and development of new diagnostics tests is necessary to the control of disease. Our group performed a study in different areas in southeast of Brazil, with acute and chronic patients. The samples of serum and feces of patients were collected and submitted to Kato‐Katz and ELISA to diagnostic. Positive patients were treated with praziquantel and monitored after treatment. Western blotting analysis using cercariae, adult worms and eggs antigens was applied to these samples for screening of immunoreactive fractions. Some fractions were more immnunoreactive to specific phases and others decreased the intensity after treatment. Five fractions were selected to compose a diagnostic kit: two with 18 and 25 kDa to detected acute phase and one with 22 kDa to chronic phase, all of cercariae newly transformed antigens; one with 50 kDa to detected acute and chronic phase and two with 17 and 20 kDa to detected the post‐treatment phase, all of egg antigens. These fractions will be indentified and recombinant proteins produced to confection of an indirect diagnostic based in lateral flow methodology. This assay is fast, simple, requires less equipment, and is an accurate tool of screening for low resource‐regions. Grant Funding Source: Supported by Capes, CNPq, Fiocruz, PDTIS (Brazil), Fiotec, UFSJ

The CD‐209 gene encodes a glycoprotein expressed as soluble or membrane, mainly present in human macrophages and dendritic cells. It is responsible for initial adhesion of the dengue vírus (DENV) to these cells. This gene undergoes alternative splicing, which results in thirteen different transcript of isoforms and consequently of the glycoprotein. The aim of this study is to predict the molecular structure of CD‐209 isoforms with carbohydrate recognition domain (CRD) modified due process of splicing alternative. The isoforms were obtained from the GenBank and aligned by Multialin software. Analysis in silico was performed to verify possible differences in CRD. 3D model structures were built by homology modeling (Swiss‐Model Server). We have demonstrated three sites of Ca2+ bind in CRD and amino acids residues that take part of it. We have found five isoforms with different CDR and only two of them keep three sites of Ca2+ bind. Validation steps were done and root‐mean‐square deviation values were found below 0.6. These variations may be correlated to the pathogenesis of dengue, since the virus needs of these sites of Ca2+ bind to interact with CD‐209 receptor. If the isoforms which miss some sites of Ca2+ are frequent in some populations this could confer a certain protection against virus infection. Future population studies would be interesting to better understand these issues.Support: FAPEMIG