recombinant protein, S. mansoni, diagnostic, schistosomiasis.

The development of a diagnosis test for schistosomiasis performs an important role in the strategies to control and eliminate the disease. Due to the change in the disease epidemiological profile, there is a need to use a diagnostic test that is more sensitive and specific than the currently available. In a study carried out by our research group, an epitope from a dopamine receptor (Sm043300e), belonging to the rhodopsin family

of G protein-couplet receptors (GPCRs), was identified by the reverse vaccinology technique. This epitope showed binding affinity for human and murine MHC II molecules and it was predicted as cell B linear epitope. Furthermore, it was able to induce the TCD4+ cells proliferation in sensitized mice by a synthetic peptides cocktail and was also recognize by antibodies present in the serum of individuals infected with Schistosoma mansoni. According to this context, the goal of this study was to produce a recombinant protein containing the Sm043300e epitope and a portion of this dopamine receptor to be evaluated as target in the serological diagnosis of the schistosomiasis. The sequence of the recombinant protein SmDOPAR.1-43r was characterized using bioinformatic tools and its expression was performed in Escherichia coli. In silico analysis, the sequence of the SmDOPAR.1-43r protein presented 85 amino acids, one theorical isoelectric point (pl) of 6,69, a molecular

weight of 9,56 kDa and it was predicted as a hydrophilic protein. The prediction analysis of functional domain showed that the domains found in the dopamine receptor were not present in the sequence used to compose the recombinant protein. The SmDOPAR.1-43r protein was expressed in E. coli BL21-CodonPlus and E. coli Arctic

Express, solubilized and purified by affinity chromatography. The SmDOPAR.1-43r was used in an ELISA test to evaluate its specific recognize by IgG antibodies in the serum of the infected individuals with S. mansoni. The ELISA test developed with the recombinant protein presented a sensitivity of 58,62% and specificity of 54,55% with a cutoff of 0,3711. According to these results, the SmDOPAR.1-43r protein did not prove a good target to serological diagnosis of schistosomiasis.