Seleção de um painel de antígenos biomarcadores de Schistosoma mansoni através de análises do proteoma sorológico / Selection of a panel of biomarkers antigens of Schistosoma mansoni by analysis of serologic proteome

RESUMO

Apesar do grande esforço na tentativa de controlar a esquistossomose, esta doença continua sendo uma das mais prevalentes no mundo. Novas intervenções são uma prioridade importante para a eliminação da esquistossomose, uma vez que o controle da doença tem sido baseado essencialmente na quimioterapia, a qual não previne a reinfecção. O desenvolvimentode uma vacina para a esquistossomose para proteção a longo prazo, bem como de um novo teste de diagnóstico, constituirá um grande avanço para o controle da doença. A compreensão da resposta imunológica associada com os estados de infecção/proteção pode constituir a base da descoberta de novos antígenos biomarcadores para vacina e diagnóstico para a esquistossomose. Recentes avanços na área pós-genômica têm permitido uma busca mais racional por biomarcadores. Inicialmente, eletroforese bidimensional (2-DE) de extratoproteico total de diferentes fases de desenvolvimento do Schistosoma mansoni foi realizada, obtendo-se um perfil de separação de spots proteicos com boa resolução com os extratos de todas as fases, mas com um perfil distinto entre eles...

ABSTRACT

Despite intensive efforts to wards schistosomiasis control, the disease is still one of the most prevalent in the world. New interventions are a high priority for the elimination ofschistosomiasis, since the disease control has been essentially based on the use of chemotherapy,which doesnot prevent reinfection. The development of a long term protection and an effective diagnostic assay would be a major breakthrough for schistosomiasis control. Understanding which aspects of the immune responses are associated with infection/protections tatus may constitute the basis for the understanding of a successfulvaccine and could also indicate new diagnostic candidates. Progress on post genomic technologies resulted in the development of rational and global approaches for the discovery of new bio markers. Initially, two dimensional electrophoresis (2DE) of different developmental stages protein extracts ofSchistosoma mansoni were conducted.It was obtained a good separation pattern of the spots that was distinguishable in all the stagesevaluated. Subsequently, twodimensional electrophoresed S. mansoniadult worm protein extracts, total and tegumental, were probed with pooled sera of infected (INF),non-infectedindividuals from endemic area (NE) andnon-infected individuals from non-endemic schistosomiasis area (NI) in a two-dimensional Western-blotting experiment (2D-WB). Atotal of 47 immunoreactive proteins were identified by mass spectrometry. Although most of the protein spots were immunoreactive to all of the serum pools, nine reacted exclusively withthe INF serum pool, and one with the NE serum pool. Glycoproteins were identified in the S. mansoni adult worm total protein extract usingPeriodic Acid–Schiff base method and lectin-blotting. However, periodate/borohydride treatment indicated that the glycoprotein glycanportion had no influence on the immunoreaction obtained in the 2D-WB experiments using different serum pools. Western- blotting of ...