Galectin-8 in the experimental Trypanosoma cruzi infection

CARLA PASCUALE; ADRIANO BERTELLI; HERNAN GARCIA RIVELLO; GABRIELA LEVY; MARIA VIRGINIA TRIBULATTI; CAMPETELLA, OSCAR; MARÍA SUSANA LEGUIZAMÓN

Honolulu

Congreso; Joint Meeting of The Society For Glycobiology and the Japanese Society of Carbohydrate Research; 2014

Galectin-8 is distributed in different tissues and in the endothelium, which links it to various processes such as migration, apoptosis induction, and platelets activation, and to the role as pro-inflammation molecule. No information is available on Gal-8 in infections by Trypanosoma cruzi, the agent of Chagas disease. This protozoan induces megaviscera and/or cardiomegaly on 20% of infected patients, during the chronic phase of the disease. We started said analysis assaying various murine infection models combined with T. cruzi strains to induce different evolution. We studied Gal-8 expression in different organs during the acute period of the infection in BALB/cJ mice (60 day old males), using the RA strain (DTU TcVI). Assays were conducted at 17 days post-infection (dpi) with parasitemia levels ranging 7x105-1.5x 106 trypomastigotes/ml. qRT-PCR showed a significant decrease on Gal-8 expression in infected mice hearts while in liver, spleen and skeletal muscle they were similar to naive mice. Organs were analyzed in triplicate and normalized to host beta-actin expression. C57BL/6J (WT) and Gal-8KO four month old males were infected with the Ac strain, (DTU TcI), which induces chronic infection (survival 90%). Parasitemia were similar between groups (followed up to 80 dpi). At four months pi, Gal-8KO mice showed an even more advanced splenomegaly than that developed by infected WT mice, while the heart's and liver's weight were similar between groups. The weight of Gal8-KO mice's spleen was 0.49±0.28-0.58g, significantly larger than the infected WT counterpart, 0.18±0.16-0.21g (p=0.0079), and normal WT and Gal-8KO's. Spleen weight obtained from WT infected and normal mice showed also significant differences (p=0.0079). HE-stained tissue samples showed greater degree of follicular hyperplasia in Gal-8KO along with numerous secondary follicles, a higher number of centerblasts and a pronounced amount of plasmocytes, when compared to WT both infected and normal. In Gal-8KO, while follicle structure is maintained, there was important lymphocyte movement towards the red pulp. These preliminary results show, for the first time, that T. cruzi modulates Gal-8 expression. The splenomegaly seen in Gal-8KO mice could suggest the involvement of this galectin in the development of polyclonal activity, a hallmark in T. cruzi infection.