EARLY TREG CELL DEPLETION DURING TRYPANOSOMA CRUZI INFECTION PROMOTES CD8+ T CELL IMMUNITY AND PARASITE CONTROL IN THE ACUTE AND CHRONIC PHASES

ARAUJO FURLÁN CL; BOCCARDO S; RODRIGUEZ C; MONTES CL; GRUPPI A; ACOSTA RODRIGUEZ EV

Congreso; REUNIÓN DE SOCIEDADES DE BIOCIENCIAS 2020; 2020

We reported that after Trypanosoma cruzi (Tc) infection, Tregs undergo a marked and sustained reduction in frequency. This naturalcontraction of the Treg response was critical to allow the emergenceof protective anti-parasite CD8+ T cell immunity in the acute phase.Accordingly, we previously demonstrated that Treg depletion at day(d) 5 post-infection (pi) but not at d11pi impacted on the magnitudeof anti-parasite CD8+ T cell response and the ability to control parasite replication in the acute phase. Considering this, we hypothesized that Tregs may exert a role during early events of T cell priming. To test this, DEREG mice were infected with Tc and injected withdiphtheria toxin (DT) or PBS at d5 and 6pi. The next day, DT-treatedanimals showed increased numbers of B cells, monocytes and neutrophils in the spleen compared to controls (p