Structural and immunological characterization of sulphatides: relevance of sulphate moieties in Trypanosoma cruzi glycoconjugates.

ACOSTA D.M,; SOPRANO LL; FERRERO MR; ESTEVA MI; RIARTE AR; COUTO AS; DUSCHAK VG

PARASITE IMMUNOLOGY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: San Francisco; Año: 2012 vol. 34 p. 499 - 510

0141-9838

Sulfoglycosphingolipids, present on the surface of a variety of cells, participate in adhesion processes and in the regulation of different cellular events. However, little is known about the structure and the role of sulfatides in Trypanosomatids. Herein, sulfated dihexosylceramide structures composed mainly by sphingosine as the long chain base acylated with estearic acid have been determined for the first time in Trypanosoma cruzi epimastigotes by UV-MALDI-TOF-MS analysis. Previously, polyclonal rabbit antibodies specific for cruzipain, the major cysteine proteinase of T. cruzi, and its C-terminal domain were developed. Interestingly, inhibition ELISA assays using cruzipain as antigen and both specific sera pre-adsorbed with increasing amounts of sulfatides prior and after desulfation treatment have demonstrated that i) sulfate is a common epitope between cruzipain and sulfatides of T. cruzi, ii) this cross-reactivity is found in the C-terminal domain, and iii) the existence of other antigenic determinants in the glycolipidic structures. These features provide evidence that sulfate groups are antigenic in sulfate-containing parasite glycoconjugates. Furthermore, sera from chronic Chagas disease patients showed that IgG2 antibodies inversely correlates with disease severity, suggesting that IgG2 antibodies specific for sulfate epitope from sulfatides   might be associated to an efficient protective immunity and be considered potential surrogants of the course of chronic Chagas disease.