RESUMO
Taeniids exhibit a great adaptive plasticity, which facilitates their establishment, growth, and reproduction in a hostile inflammatory microenvironment. Transforming Growth Factor-ß (TGFß), a highly pleiotropic cytokine, plays a critical role in vertebrate morphogenesis, cell differentiation, reproduction, and immune suppression. TGFß is secreted by host cells in sites lodging parasites. The role of TGFß in the outcome of T. solium and T. crassiceps cysticercosis is herein explored. Homologues of the TGFß family receptors (TsRI and TsRII) and several members of the TGFß downstream signal transduction pathway were found in T. solium genome, and the expression of Type-I and -II TGFß receptors was confirmed by RT-PCR. Antibodies against TGFß family receptors recognized cysticercal proteins of the expected molecular weight as determined by Western blot, and different structures in the parasite external tegument. In vitro, TGFß promoted the growth and reproduction of T. crassiceps cysticerci and the survival of T. solium cysticerci. High TGFß levels were found in cerebrospinal fluid from untreated neurocysticercotic patients who eventually failed to respond to the treatment (P = 0.03) pointing to the involvement of TGFß in parasite survival. These results indicate the relevance of TGFß in the infection outcome by promoting cysticercus growth and treatment resistance.
