O papel da proteína rP21 na replicação parasitária in vitro e na infecção aguda experimental por Trypanosoma cruzi

Abstract

Trypanosoma cruzi P21 protein (P21) has been associated with several biological activities, such as induction of phagocytosis and actin cytoskeleton polymerization. In this study, we investigated the role of P21 on parasite replication and its effect on acute experimental infection. We observed that recombinant P21 (rP21) decreased the multiplication of the G and Y strains of T. cruzi in C2C12 myoblasts. This phenomenon was associated with greater actin polymerization and production of IFN-γ and IL-4. During experimental infection, lower cardiac nests, inflammatory infiltrate and fibrosis were observed in mice infected with the Y strain and treated with rP21. In rP21-treated mice, the observed increase in the expression of IFN-γ was counterbalanced by high levels of IL-10, which was consistent with the lower cardiac tissue injury found in these mice. We have also seen that upon stress, T. cruzi produced more P21. The increase in P21 production and the consequent control of parasite replication suggest that P21 is one of the soluble factors that lead to parasite dormancy, resulting in the perpetuation of T. cruzi infection in the host.