La infección por Trypanosoma cruzi en ratones gestantes induce una respuesta inmune celular con producción de citocinas en sus fetos

the objective of this study was to detect the cytokines ifn-g, il-4 and il-10 expressed by cd4+ t cells in tissues of fetal mice with acute chagasic infection. for this, we examined the fetuses of nmri mice whose mothers were infected with 22×103 metacyclic trypomastigotes of the m/hom/bra/53/y strain of t. cruzi and made pregnant during the acute phase of infection. for the detection and localization of inflammatory infiltrates, nest parasites, antigens of t. cruzi and cytokines we used hematoxylin-eosin techniques, peroxidase-anti-peroxidase and immunofluorescence. the immunohistochemical study revealed the presence of inflammatory infiltrates and antigens with amastigote nests in fetal skeletal muscle. cd4 + t cells producing ifn-g, as well as deposits of ifn-g and il-10, were detected in sections of placenta, heart and skeletal muscle of fetuses of mice infected, while cd4+/il-10+ was found only in skeletal muscle; in addition, deposits of il-4 were detected only in placentas of healthy mice. these results indicate that fetuses are capable of generating their own immune response to antigens transmitted by their mother, which induces the secretion of cytokines and that, acting in synergy with the maternal antibodies, confer them a state of protection against infection; and that the transmission of the parasite depends on factors specific to each mother, which may modify its ability to control such transmission at the placental or systemic levels