Specific antibodies for sulfate moieties present in the N-glycans from the native C-T domain of cruzipain play an enhancer role in the immunepathogenesis of experimental Chagas disease

SOPRANO, LL; ACOSTA, DM; FERRERO, MR; GARCIA, GA; ESTEVA, MI; COUTO, AS; DUSCHAK, VG

Mar del Plata

Congreso; IX Congreso de Protozoología y Enfermedades Parasitarias.; 2011

Soc. Argentina de Protozoologia

Specific antibodies for sulfate moieties present in the N-glycans from the native C-T domain of cruzipain play an enhancer role in the immunepathogenesis of experimental Chagas disease. L.L. Soprano 1, D.M. Acosta 1, M.R. Ferrero1, G.A. García1, M.I. Esteva 1, A.S. Couto3 and V.G. Duschak.1 1Inst Nac Parasitol Dr Mario Fatala Chaben, ANLIS-Malbrán, Ministerio de Salud , Argentina; 2CIHIDECAR-Dpto.Q.Org., FCEN, UBA, Argentina. Trypanosoma cruzi contains a major cysteine proteinase, cruzipain (Cz). This lysosomal enzyme bears an unusual C-terminal domain (C-T) that contains a number of sulfated high-mannose type oligosaccharides as post-translational modifications and is responsible for most antibodies in natural and experimental infections. Interestingly, mice immunization with C-T domain has shown that sulfate moieties of Cz molecule are able to elicit specific immune responses. In order to evaluate the involvement of sulfate moieties in the immunepathogenesis of experimental Chagas disease, BALB/c mice immunized with C-T prior and after desulfation treatment, were further sublethally challenged with trypomastigotes. Mice immunized with C-T showed higher IgG1/IgG2a ratios than those immunized with the sulfate- depleted C-T and the humoral immune response to sulfates was mainly IgG2b. By contrast, sulfate-depleted C-T immunized mice produce dominant IgG2a antibody responses. Citoquines profile showed high levels of IL-4 in C-T immunized mice, and levels of IFN-γ increased in supernatants of stimulated spleen cells of mice immunized with the sulfate-depleted antigen. The immune response in C-T immunized mice resulted Th2 and ultrastructural abnormalities were evidenced in cardiac and skeletal muscle. Surprisingly, pathological alterations were not observed neither in skeletal nor cardiac muscle tissues from mice immunized with sulfate-depleted-C-T. In addition, a lower labeling was observed by immunogold-electron microscopy using myosin-adsorbed sera specific for Cz and C-T compared to C-T immunized mice in both tissues. After, sublethal challenge, mice group previously immunized with C-T showed the highest mortality and those that survive, showed: 1) pathological abnormalities in skeletal muscle tissue; 2) calcium deposits with mononuclear inflammatory infiltrate cells in skeletal muscle; 3) higher levels of CPK, LDH, AST (damage marker enzymes) than mice previously immunized with desulfated C-T. In accordance with our results it can be assumed that a causal relationship exists between the presence specific antibodies for sulfates in the sera and/or sulfates from C-T as enhancer factor and the development of some of the pathogenic mechanism involved in muscle immunepathogenesis of experimental chronic Chagas disease. Supported by CONICET-ANPCYT-UBA.INP-ANLIS-Malbrán